Is this a tutorial? 
Did you mean GNOME 43? 
Please edit your topic title accordingly.
You keep using that word in different ways and I have no idea what you mean by it.
It sounds like you removed packages you shouldn’t have, but without knowing what you removed, I can’t tell you what to reinstall.
Check your Pacman log and look for the timeframe this may have happened.
grep -i removed /var/log/pacman.log