ok so i think i can buy a gun!!! best long gun to shoot your head off with?

just caught a glimpse of myself in the mirror today. i know nothing about guns, i looked it up and i can buy guns here as long as they're "long guns" (not handguns). any suggestions? I have no clue what I'm getting, I just need something that i can point at my head and pull and its over. i dont want to talk to ppl at the gun store bc idk what i would tell them when they ask what its for (hunting?). so if someone could list off some makes/models and ammunition that goes with it that would be good. i want something that will 100% work, ive heard of too many times where somebody shoots themself and survives.

bonus: i will livestream it on here/WPD if someone helps me out. someone help this stupid tr'anny die please