Every child is different and so is their skill level, so when deciding on the right drills it can be difficult. Choose a variation of different drills at several difficulties and just gauge where your child is at. If a drill is too difficult and they can’t quite seem to get it, pick an easier one and let them work their way up to it.
This comes back to allowing your child to enjoy the game first and then developing that drive a little later on. You are going to work the hardest at the things you enjoy doing the most and this is the same for your child.