HOW do you get through working 12 hour shifts?

B

I literally cannot function straight after working 12 hour shifts. I’m 6 weeks and the exhaustion is real. I don’t know what to do. I’ve asked for 8 hour shifts. I need a job. But I feel almost drunk half way through the day because of how tired I am. I just want to cry. I cannot handle 12 hour shifts anymore. Someone give me some advice PLEASE.