but it’s not an ADHD “pick up every hobby” friendly one

That’s true. I was in luck and there was a blacksmith in town who opens his workshop to kids on occasion or travels to job conventions and brought his tools with him. Maybe there are comparable activities/ offers near you, which I can highly recommend. Not only will you not have to worry about tools and materials, most importantly there will be a “teacher” around.

If you find something and decide to check it out, have fun! :)