Your son sounds very active at this point in time. It is unusual for a child with mild to more severe attention problems being able to sit and listen to parents reading aloud to them. You may be reading books that are of high interest to him and he may enjoy the intimacy and attention of being read to by his parents which is not always true of a school situation. Whether he is just active or has mild or more severe attention problems he will do best with plenty of exercise/ physical activity, structure in his environment such as regular routines for bedtime, mealtime, quiet time
(playing puzzles/games, limited screen time, artwork/crafts, etc.) and consistent expectations. When you give him directions make sure that he is facing you and listening, limit to no more than 2- 3 steps at his age and then have him repeat what they are. Then supervise and encourage him so that he realizes that you are serious about what you are asking him to do. So easy for children to tune out parents who talk a lot and don't follow through. Help him develop decision making by giving him 2-3 choices to choose from about what he wears, eats, how he spends his quiet time, his physical activities, his chores, etc.) . Spend time talking about the consequences of choices he makes -good and bad. This helps him feel more confident and develops his executive functioning which includes judgment, initiating (starting something), monitoring his emotions, time management, etc. My best to you and your son.