Hello, I'm not very computer confident but did install Ubuntu ok onto my old Surface Go tablet. It worked okay , but the webcam didn't function, in trying to fix this, I followed some advice in a chat on Git hub but now I cannot run ubuntu at all on my machine

All I get is a black screen with some basic command line information. I am asked to log in using my user name and password. And then I just get a blank command line.

I disabled secure boot and tried to reboot from a USB. But I think that the changes I made in trying to get the webcam to work, have now disabled the USB port too as nothing happened when I tried to do that.

Any help would be greatly appreciated.