10yo need no online courses.
At this stage you need to develop his cognitive ability and coordination skills
1. Buy him Lego lots of lego, Lego is the best way to boost your child's creativity and It literally opens their mind.
2. Art and craft
3. Board games - Monopoly, Scrabble
4. Puzzles
5. Card games
6. Mechanix
Just don't put him in front of tv/ipad/computer screen just because you yourself don't want to entertain with them or you want to watch your own dumb tv show.