I’m not advocating anyone buy a gun, mind you. My general opinion on guns is the same about cars: the only person I truly trust to operate one is me; the rest of all y’all are just generally unreliable.
That said: get a long gun. Any non-Bulpup rifle with a 20” or longer barrel - it’s really hard to commit suicide with a long rifle. You can find a way, sure, but there are far easier, more reliable ways to off yourself than trying to figure out how to pull a trigger you can’t reach when the bangy end is pointed at your head. And the knowledge that most people who try doing this end up still alive but permanently mangled and with reduced faculties may drive you to seek those alternative methods.
Another plus for a rifle is that it’s simply a better weapon for killing fascists. We have a lot of evidence that handguns are almost never used in armed conflicts. They’re far less powerful than rifles (in general), and their effective ranges are drastically shorter. Get a cheap optic, do some practice shooting, and you’ll be better armed and prepared than any open-carry idiot running around armed only with their trusty Colt M1911 with official Trump pistol grips.
I really wish that last part was a joke.
I don’t mean to come across as minimizing mental health issues. I also can’t prevent you from trying to off yourself. All that said, I hope you are able to get help, and get healthy.