1 month till college starts, what to do

My college starts September 1st week and till then I have nothing to do so please recommend me something. • can’t do physical stuff like gym or cycling as I have a fractured right arm • don’t have money to go out every now and then and I want to do something that’ll keep me occupied for a month • I get bored watching series or movies now since I’ve been doing it for like 2 months already • I read books but don’t want to rn • not going to learn something beforehand that I’m going to learn in college like coding etc • I used to play chess and I was like crazy for it so I can do something like that and I also enjoyed playing minesweeper but it got repetitive, chess I might start but considering these games please recommend me something of that sorts • I don’t want to play mobile games • I want to do something that is fun, interesting, requires practice and researching to get good at, just like chess as I said Based on these things, please recommend something, I’m writing it here because I’m sure there might be someone who knows about something interesting and different that they do or did which they think I might find interesting.