What should you do when you like a guy 4 years older than you whos your best friend and you think he thinks youre annoying and talk to much but he doesnt know that you like him?

You need to wait out and find out what he likes without stalking him. You want to do whatever you can to match what he likes, then he'll start liking you. You should then start flirting and maybe you'll end up with a boyfriend :D