Oooh, swimming is rly cool for this. When going swimming with your friends it's easy to alternate between playing or whatever and swimming with proper form for as long as possible. It may not be a replacement for a complete workout, but I like to use it as a substitute for triceps and lat workout for instance. Apart from that, I think it's good for like lung capacity and it's also healthy for ur joints. Other watersports concerning: I did some Kajaking last summer and I gotta tell you, ur arms are gonna be sore af from that. Only bummer is, ur legs are left out completely there.
Apart from that, I personally think running in itself is fun. But thinking of actually fun ways to run, then Football, Baseball or Parkour come to mind. Since I know a person that hates running, but loves cycling, ig cycling is a good substitute for running.
Presently, I prefer to just do weight lifting. Since I'm still a student, i also get to do other sports easily, as that is a mandatory subject. Once i'm finished with school tho I imagine I'll stick with weight lifting. Tho I'm itching to try out MMA as well. Jiujitsu is another sport u may wanna try out. I did it for a few years and it's a very social sport where ure bound to meet new ppl.
Hope this helped OwO