Anyone know how to fix Mac books? My laptop just turned off .. (OnlyFans)

Anyone know how to fix Mac books? My laptop just turned off last night and won’t turn on. Before it turned off the screen went black and a file sign showed up with a triangle and ! In the middle and she won’t turn on. I’m literally In mourning haha. It’s got my uni work on it so any help to get that back would be very much appreciated!!!! It did make a creepy sound before it turned off like a cracking sound you’d hear in horror movies, I was very spooked 😱 - gona use my sisters laptop for movie night tomorrow so don’t worry guys!