How to set default fonts in Mac?
Open Terminal and run these commands: (Restart after)

rm -rf ~/Library/Caches/*
 rm -rf ~/Library/Saved\ Application\ State/*
 sudo rm -rf /Library/Caches/*
 sudo rm -rf /System/Library/Caches/*
 sudo rm -rf /var/folders/*
 atsutil databases -removeUser
 sudo atsutil databases -remove
 sudo atsutil server -shutdown
 sudo atsutil server -ping

Restart

Reset Standard fonts in Font Book


Open Font Book. File -> Restore Standard fonts. Restart.