Please use the fully-qualified name (e.g. shivammathur/php/php@5.6) to refer to the formula.

[Chemees]

➜  ~ brew-php-switcher 7.2
Switching to php@7.2
Switching your shell
Unlinking /usr/local/Cellar/php@7.2/7.2.34_4... 0 symlinks removed.
Unlinking /usr/local/Cellar/php@7.4/7.4.29... 0 symlinks removed.
Unlinking /usr/local/Cellar/php/8.1.5... 24 symlinks removed.
Error: Formulae found in multiple taps:
       * shivammathur/php/php@5.6
       * exolnet/deprecated/php@5.6

Please use the fully-qualified name (e.g. shivammathur/php/php@5.6) to refer to the formula.
You will need sudo power from now on
Switching your apache conf
grep: /etc/apache2/httpd.conf: No such file or directory
Password:
sudo: a password is required
grep: /etc/apache2/httpd.conf: No such file or directory
Password:

or

brew link --overwrite --force shivammathur/php/php@8.0

Both is same.

[Shivam Mathur]

Tap exolnet/deprecated is longer maintained, So you can remove it.

HOMEBREW_DEVELOPER=1 brew untap exolnet/deprecated

Then run brew update and try again.