I'd like to give him good advice but honestly, I have no clue what the world is going look like even 3 years from now.
My oldest boy is a lifeguard. They’re in demand! Some facilities offer lifeguard training starting at age 15 (second son is taking it this summer). First-aid training is also valuable, and reasonably priced at a county Red Cross facility.
Maybe if you let his computer get so messed up it didn’t work at all, he’d be motivated to learn more about its operation and maintenance. My reply for any electronics issues is “Don’t talk to me, I have no idea.” They either figure it out on their own, or get help from their Dad, but he makes them pay with extra labor.