So, I was stupid enough to deactivate the graphic card (actually one of the two graphic cards) on my laptop.
Now, I just get a black screen when I start my computer. What could I do? Thanks in advance.
Solved the problem.
In case it would interest someone :
-I closed and unplugged the computer, removed the batteries, put them back, started the computer and from there I was able to start in safe mode and reactivate the graphic card.