I am professionally a software developer for 8 years and I simply don't have ideas for personal projects (Can't find any problem that I can fix with programming). At times I feel like that's natural and I shouldn't worry about it. But on the other hand, I do like to imagine having something personal that I can work on so that even if some days on my main job are not satisfying, I can always work on my hobby project and find that missing satisfaction.
End goal here is obviously to get better sleep as sometimes my mind feels dissatisfied with the day's work.
Funnily, I day-dream about the idea of already having done the boring parts (simply manifesting a project that already exists) of some personal project and only solving exciting problems in relation to adding a new feature or exciting aspects.
This creates a problem as I hate staring at a blank file not knowing what to write.
Are you physically active? If no, then I'd suggest taking up a sport. Whether alone or with others, physical activity is extremely important, and it can be a rewarding hobby.
If that's already covered, then I'd ask: would you prefer to have a hobby that you do alone, or with a group?
For group hobbies, you can browse meetup.com, that's how I found my table-top RPG group, and we've been having loads of fun together for...about 15 years now.
(TTRPGs are my favorite, pathfinder 2e is the best ever)
For alone hobbies, I'd say the most important aspect is stay away from the screen. Music is a common one, or another type of art. Painting can be extremely rewarding, even if you have no talent.
I like to do MOC lego projects. (basically, use legos to make your own creations) I build mecha out of lego technic and bionicle/star wars parts.