You have a Nvidia 750 Ti, ist that right?
When I saw that right, You need the 390 Drivers. Here You have 2 Options:
-
Because the Driver isn't compatible with the used 6.8 Kernel but available in the Repo's, You could install an older Kernel like the 5.15 Kernel and then install the 390 Driver from the Repo's. For the Kernel take a Look at this:
Nvidia 390 drivers on kernel 6.8 - #6 by Ponce-De-Leon -
You stay at the 6.8 Kernel and add this PPA to get the 390 Driver:
But before You do something of that, I would recommend to switch to X11/Xorg because You are using a Nvidia Card. To do that, go to the Login Screen (not the Lock screen). Simply reboot for that. On the Login Screen, click on Your Profile so that the Password Field appears. When it is appeared, You should see a Gear Icon in the bottom right Corner. Click on it and choose the Option ''Zorin Desktop on Xorg'' and then log in.
Then, removing maybe installed Nvidia Drivers could be a good Idea before installing new one's. to do that, type in the Terminal sudo apt purge nvidia* to remove them.