I wanted to learn piano, or violin. I am not sure I could learn either one now, because of pain issues. I also wanted to learn at least two languages, and I do understand and speak a little Spanish. I could probably still learn to improve the Spanish at least.
I used to write and I could draw a few things here and there. I paid attention in art class as a kid and used some of what I learned to design a T-shirt for Science class when I was 12. We were competing against other students and other schools for the top prize and the winning shirt went onto be displayed at a museum in San Antonio, TX. I never thought I'd win, but much to my surprise, I won first place and off to the museum it went. My mom kept one of the shirts and my dad still has it to this day.
And another one of my mainstays at the time was the late, great Microsoft Paint. I spent many hours using that program and rendered a computerized starboard side profile of the Edmund Fitzgerald when I was younger using the blueprints. It was one of many things I did and it's something that I enjoyed. Shortly after I finished it, however, my computer at the time went down with a virus and I didn't back up the file. I was heartbroken enough over that I no longer had the drive nor interest to do that anymore.
Another thing I loved to do was write fan fiction mainly for Star Wars using characters from the films with a few of my own. I never let anyone read it but the last one I wrote was probably several pages long. Never to late to pick back up a mechanical pencil, make use of WordPad or find an older version of MS Paint and start all over again. But these were all very serious hobbies at one point.