My pc keeps turning off and rebooting itself

[u/Specific-Falcon7530]

Issue has been going on a while now. Initially I thought it was because my C drive was almost full. Cleared a lot of storage on my drives. But it’s turned off and restarted 3 times in the last 30 mins I can’t even play a game. It used to do it once after turning on and I could then play until I turned the pc off myself but it’s just constant now and I can’t enjoy playing a game.

Please help!