This isn't a hobby, but most of my hobbies fall into this: building stuff is what makes me happy.

Does disc golf count?

Baby making

Pinball

Cannabis!

Jiu-Jitsu! Make friends, and smash them!

What’s fun is going to be individual, isn’t it? I absolutely love going to museums. Science, art, history, whatever. I live somewhere with a lot of museums, so I look into discount programs and plan day trips around seeing exhibits that sound interesting. Obviously that won’t work for you if you don’t care about museums or don’t have many nearby.

There’s nature everywhere, even in cities, and I enjoy using apps like Seek or Merlin Bird ID to help understand what I’m looking at. It’s fun to keep my eye out for new plant species, and helps me learn what’s around me locally.

shooting fish?

I really enjoy tinkering with stuff and repairing it if I can. Doesn't matter what. It's satisfying keeping stuff out of the landfill.

Probably not 'barrels' of fun, but at least a couple of buckets' worth.

Scuba Diving. I'm lucky if I can go twice a year but just thinking about scuba diving feels like a full-time hobby

Mountain biking. Ridiculously fun especially when you have good trails and a good bike.

Designing and creating fantasy worlds, characters, props, and creatures with drawing/painting/digital art (aka concept art and illustration). Or just making art in general. It's fun to be imaginative, to create things, and to tell stories.

Looking at other people's art and being immersed in video games is a lot of fun for me because it takes me out of reality for awhile. I enjoy pretending to be a character in Cyberpunk 2077, for example, whenever I look at the pre-production work the artists did.

Cleaning floors, bathroom, sinks, etc. /organizing stuff in my house is also fun to me because I find it meditative. I like my environment neat and tidy to do my other hobbies. Or Im just getting old that I like doing chores (when no one is telling me to do it).

Waiting to see what others answer because got no actual hobbies since having kids…

Playing roller hockey with my mates

Judging by the games I play and how I generally react to them: Getting angry and frustrated.