I don't want to undermine everyone's suggestions but I think they are failing to understand this is a kid, buying him a laptop and stuff is okay but doesn't motivate him to much.

Check for authors of books for kids. Invent with python is great, that was going to be my suggestion. But same author has plenty, like this one https://turtleappstore.com/book/ ... to echo someone who mentioned Minecraft (indeed, already marked a whole generation into computer science subject!). Good luck! Maybe you can even find something for you, like, how do we teach CS/ programming to kids? How come that moving the Logo turtle was alright for so many years, lol