My laptop won't start, what should I do?

Every time I start my laptop I have to type some command. I've had this before and my friend told me what to enter

and then I was able to start the laptop again somebody knows by chance what I have to enter to get the laptop up and running again, some command or something that has to be

Try it, write "exit"

Then something should come:

/ dev / sda1: Unexpected…
fsck exited…
The root filesystem on / dev / sda1 requires manual fsck.

Then you write:

fsck / dev / sda1

If that doesn't work, write what kind of "error" or message comes up.

Okay, I'm just doing it

Thank you for your help

No problem:-)