tl;dr: Don't be fooled. Stay out of prison.
Long version:
Someone you may know or don't know says that they need a check cashed and that they will pay you some amount for doing so. You will get caught and your friend will disappear. Depending on the amount of the fraudulent check, it may be a prison sentence. Your credit rating will be toast. So, don't be tempted with some fast cash deception. Please.
I think that I am watching way too many True Crimes podcasts.
Tiny note: Very wealthy people can commit any number of crimes and thatdue to their wealth and connections may not face consequences. If you ain't very wealthy, don't do dah crime! The world works like that.