If you click on the Zorin logo at the bottom left of your screen, and you then click on SETTINGS. Scrol down and click on ABOUT. You will find your gnome shell version that your system is using there.
If you are on Zorin OS 16, it should say Gnome Shell 3.38
Additionally, you can also get information about your system by entering a terminal via these commands.
sudo apt install screenfetch
When asked hit the
Once installation is completed, simply type
You will discover solid good info there. And don't forget
uname -a in terminal to just see what version of kernal that you are using.
And lastly, if you would detailed information about your entire system, I recommend installed HARDINFO, which can be found in the software center. Once installed, it will show up as System Profiler in your APPS list.