Have you tried going into Settings > Appearance > Zorin Appearance > Layout and swapping the themes back and forth? (I'm also coming from Windows as of a few days ago!)
If it doesn't help install gnome extension manager
sudo apt install gnome-shell-extension-manager
open it and go to tab "installed". Take a look if Zorin taskbar is enabled there and also Zorin menu.
If you have installed other third party gnome shell extensions disable them for testing.