I'm 55, young (I think) fit and active. According to my Garmin I have the fitness age of a 20yo. I'm definitely fitter than I was at 20!
My local community centre hosts a council run over 50's club, where for a very small annual membership you can attend dozens of weekly activity sessions.
They do things like "exercise with arthritis" and chair yoga, which wouldn't interest me, but also various arts and craft sessions, and things like cribbage, bowls and croquet.
I've never been creative, but I'd like to have a go, and some of the games might be fun, but it's probably mostly attened by people older than me, despite the name.
I've retired early and have some time to spend on new projects and new skills, but will doing it this way make me old before my time?!