You don't want to die, you just want to get out of the toxic environment that you're currently in. This is hard, I know, I have no idea how your school system works etc, but you have to get out of the place you're in. Even if it results in failing a year and repeating it, do whatever you can to switch school or class.
I know it's risky to write, but I also think you're starting to see things that are not necessarily there. Just because someone is saying something near you that you cannot hear, doesn't mean that it's about and against you.
Remember, words can hurt only as much as you let them, and there is no one who can hurt you more than yourself. You are a valuable human being. You have flaws like everyone else. But you are NOT worse than the others! Stay strong, these days will pass no matter what you think.