Seconding the home lab / micro controler project. A bit of research and you can get most things (especially shitty IOT crap off amazon) to dump their firmware and let you go digging around in usually lazy code. (A friend and I took apart an automated water bowl for a cat the other day, took a few hours, but we now have the tools and know what to search for on the next time someones shitty internet enabled fish feeder dies)

The reason is that in [current year], knowing stuff is great, but knowing where to find the info you need is more important. Thats why AI is taking off like it is. Its users ask in plain text for answers to things, the resourceful people only use that as a tool to find what they need not the complete answer(Also keep good notes. So you only have to find something once).