How do I enjoy something?

Tldr;
How do I learn to enjoy something so I don't feel like I'm missing out?

It may help if you just go out and do those things and don't let your idea of what it might be like get in the way.

Stop over thinking and enjoy the ride of life. Spending time with friends is enjoyable itself. If you don't enjoy an activity you can't force yourself to enjoy it.

In the case of roller coasters, I find the fear to be part of the fun. The anxiety when you're in line, waiting to get on and finally get strapped in, the ride takes off and you aren't in control anymore, just along for the ride, literally. The anxiety when slowly climbing to the top, the view, the first fall and the feeling of freefalling, the win in your hair the g-forces, and finally the catharsis of conquering the ride. Its hard to boil down any one experience to a single atom of enjoyment, but I hope that can explain why I enjoy thrill rides (and others too to some extent).

You're not enjoying it because you are literally doing nothing. You're merely a passenger.

Find something when you're the one in control of whether or not you fuck up. Rock climbing, downhill mountain biking, etc