How to fix Linux

I have a huge problem and I can't get into my pc (linux).

There's something in English on the whole screen and it doesn't even load or anything. Can someone please tell me how I could restart the laptop or what I should do with it? It is very important because I teach from home and otherwise I can't attend.

"Anything in English" is a bit vague. What is written there?

So it might make a lot of sense to show a screenshot of what is "on the whole screen" in English, don't you think?

PS: It's called "loads"!

You can't say anything without the error message.

Basically first:

There's something in English on the whole screen

what exactly? Would it be possible for you to provide us with a photo?

And on the subject:

because I teach from home and otherwise I can't participate

All common systems that are used for online lessons (Zoom, Teams, GoToMeeting, Skype, etc.) can also be used via smartphone.

Just ask the one who installed it for you