Have you heard of Modern stoicism? I hadn't, until I went to a philosophy and music festival called How the light gets in. There was a dude there called Massimo who talked about what you can amd can't control. Sounds simple right? Turns out, I spent loads of time stressing about what I can't control and not enough time on what I can. Every year there is a stoicism week held by Exeter University, they teach people the principles of stoicism and how to apply it to daily life. it's free to sign up, I did it once and i was more content after it than before. Give it a go!