Make sure your using the youth style ball. They don't start using a regular ball till 11-12.
When your doing drills think about them as either skill building, fitness building or both. But concentrate on what it is about the drill you want the child to learn.
Basics:
Moving/defense - Drills involving short running. Step slides, back peddle, run. These of course develop coordination quickness and moving without the ball.
Rebounding - At this age his hands are probably small but still focus on actually catching the ball. Also teach him to understand positioning and watching the ball. Rebounding is probably the hardest to teach the young but practice.
Dribbling - of course there are thousands of drills online. Just practice practice practice.
Shooting - Same thing plenty of drills. Try to help him develop good form. That's why it's important not to have a ball that's too heavy.
If your kid lacks skills to start with focus more on the moving athletic side half of basketball is defense.