Icon theme is: Shade of Shade - Black Orchis: Shade of Z - Gnome-look.org
Application theme is - Orchis: https://www.gnome-look.org/p/1357889/
The wallpaper comes with Zorin OS 16 beta
To setup/change themes, please read:
Icons: How to set a third-party icon theme
Theme: How to set a third-party desktop theme