@RiaS Hi and welcome to the forum.
A couple of questions to help steer advice on installation:
1 Are you using Ubuntu (or in the past Zorin 12) on its own or as dual-boot with another Operating System e.g. Windows?
2 Do you intend to (re)install Zorin 12 Core or Lite in place of Ubuntu 20.04?
In the meantime have a look at this:
Also, @swarfendor437 's Unofficial Manual for Zorin 12 is still available for download, (if you do not have it already). Unofficial Zorin 12.x Core Manual - still work-in-progress! - Old Zorin Forum archive