Security update works, but I can't check on Other updates on Zorin. Why I can't select it?
That last I remember, in a thread we Removed Flatpak.
The only thing I see listed in your screenshot under "other updates" is a package for use with Flatpak.
You can still resolve that, if you want. In terminal, run
sudo apt install xdg-desktop-portal
That's the update I can't select
Yes, because in a previous thread, we removed Flatpak. It is not applicable to your system.