Instruct dnf to skip confirmation dialog and assume yes for every question.

Ad hoc solution

By default you need to confirm every add/remove operation.

$ sudo dnf install which
Last metadata expiration check: 0:00:04 ago on Sun Apr 10 11:05:15 2022.
Dependencies resolved.
====================================================================================================================================================================================
 Package                                  Architecture                              Version                                         Repository                                 Size
====================================================================================================================================================================================
Installing:
 which                                    x86_64                                    2.21-27.el9                                     baseos                                     42 k

Transaction Summary
====================================================================================================================================================================================
Install  1 Package

Total download size: 42 k
Installed size: 80 k
Is this ok [y/N]: 
Operation aborted.

Specify an additional command-line option to automatically answer yes for every question.

$ dnf install --assumeyes which
Last metadata expiration check: 0:00:25 ago on Sun Apr 10 11:05:15 2022.
Dependencies resolved.
====================================================================================================================================================================================
 Package                                  Architecture                              Version                                         Repository                                 Size
====================================================================================================================================================================================
Installing:
 which                                    x86_64                                    2.21-27.el9                                     baseos                                     42 k

Transaction Summary
====================================================================================================================================================================================
Install  1 Package

Total download size: 42 k
Installed size: 80 k
Downloading Packages:
which-2.21-27.el9.x86_64.rpm                                                                                                                        165 kB/s |  42 kB     00:00    
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Total                                                                                                                                                53 kB/s |  42 kB     00:00     
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
  Preparing        :                                                                                                                                                            1/1 
  Installing       : which-2.21-27.el9.x86_64                                                                                                                                   1/1 
  Running scriptlet: which-2.21-27.el9.x86_64                                                                                                                                   1/1 
  Verifying        : which-2.21-27.el9.x86_64                                                                                                                                   1/1 

Installed:
  which-2.21-27.el9.x86_64                                                                                                                                                          

Complete!

Permanent solution

Try to remove package installed in the previous part.

$ sudo dnf remove which
Dependencies resolved.
====================================================================================================================================================================================
 Package                                  Architecture                              Version                                        Repository                                  Size
====================================================================================================================================================================================
Removing:
 which                                    x86_64                                    2.21-27.el9                                    @baseos                                     80 k

Transaction Summary
====================================================================================================================================================================================
Remove  1 Package

Freed space: 80 k
Is this ok [y/N]: 
Operation aborted.

Inspect current dnf configuration.

$ cat /etc/dnf/dnf.conf 
[main]
gpgcheck=1
installonly_limit=3
clean_requirements_on_remove=True
best=True
skip_if_unavailable=False

Assume yes for every question by default.

$ echo assumeyes=True | sudo tee -a /etc/dnf/dnf.conf

Perform any package operation

$ sudo dnf remove which
Dependencies resolved.
====================================================================================================================================================================================
 Package                                  Architecture                              Version                                        Repository                                  Size
====================================================================================================================================================================================
Removing:
 which                                    x86_64                                    2.21-27.el9                                    @baseos                                     80 k

Transaction Summary
====================================================================================================================================================================================
Remove  1 Package

Freed space: 80 k
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
  Preparing        :                                                                                                                                                            1/1 
  Erasing          : which-2.21-27.el9.x86_64                                                                                                                                   1/1 
  Verifying        : which-2.21-27.el9.x86_64                                                                                                                                   1/1 

Removed:
  which-2.21-27.el9.x86_64                                                                                                                                                          

Complete!

No questions asked.

Additional notes

Alternatively, you can change the default answer from no to yes, which is enough most of the time.

$ cat /etc/dnf/dnf.conf 
[main]
gpgcheck=1
installonly_limit=3
clean_requirements_on_remove=True
best=True
skip_if_unavailable=False
defaultyes=True

Notice, the default answer is altered, simply press enter to confirm.

$ sudo dnf install which
Last metadata expiration check: 0:18:06 ago on Sun Apr 10 11:05:15 2022.
Dependencies resolved.
====================================================================================================================================================================================
 Package                                  Architecture                              Version                                         Repository                                 Size
====================================================================================================================================================================================
Installing:
 which                                    x86_64                                    2.21-27.el9                                     baseos                                     42 k

Transaction Summary
====================================================================================================================================================================================
Install  1 Package

Total download size: 42 k
Installed size: 80 k
Is this ok [Y/n]: 
Downloading Packages:
which-2.21-27.el9.x86_64.rpm                                                                                                                        220 kB/s |  42 kB     00:00    
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Total                                                                                                                                                48 kB/s |  42 kB     00:00     
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
  Preparing        :                                                                                                                                                            1/1 
  Installing       : which-2.21-27.el9.x86_64                                                                                                                                   1/1 
  Running scriptlet: which-2.21-27.el9.x86_64                                                                                                                                   1/1 
  Verifying        : which-2.21-27.el9.x86_64                                                                                                                                   1/1 

Installed:
  which-2.21-27.el9.x86_64                                                                                                                                                          

Complete!
ko-fi