It might be worth looking at GD Quest (https://www.gdquest.com/tutorial/godot/learning-paths/gettin...) to determine if it's something your kid would want to learn and get into. As a developer, I found it very easy to start to get started with Godot versus Unity and Unreal so it might be a fun adventure for your kid to start learning :)
https://docs.godotengine.org/en/stable/getting_started/first... https://kidscancode.org/godot_recipes/4.x/games/first_2d/ind...
After that my son wanted to switch to making his own game so we've been re-implementing boss fights from cuphead and lately he wants to make an idle game.
I've also found its fun to just get them to be part of the design process in game jams. It's really great to see the creative ideas that come out of young kids and game making with kids has been super fun and educational.