See this page in the manual: http://manual.audacityteam.org/o/man/click_removal.html
Personally I never use Audacity’s Click Repair effect - I find that he ClickRepair package from Brian Davies does a truly excellent job (I use Audacity for all my other editing). See this sticky thread: https://forum.audacityteam.org/t/click-pop-removal-clickrepair-software/1933/1
You find this workflow tutorial from the manual useful: https://forum.audacityteam.org/t/click-pop-removal-clickrepair-software/1933/1
It’s part of this set of tutorials: https://forum.audacityteam.org/t/click-pop-removal-clickrepair-software/1933/1
WC