As a parent educator, I can tell you that he is used to so much negative attention that it's like a habit.
How is he in school? Many kids who misbehave in school either have no discipline at home, rule the household or have issues that have been overlooked like reading issues, vision issues, etc....
He is seven. Sit him down and tell him each and every morning he is to eat breakfast and clean up after himself. Then, you need to get both of you on bikes. Do NOT mention the bad behavior. Tell him that this is going to be the new routine. You need to be consistent ! Ride a bike w/ him for at least 1 hour. You need to turn this around. The excercise will help his behavior !
If there are other concerns, you should talk to your pediatrician. Without knowing all the facts and visiting your home, I have no true way of telling.
At seven, he should be dressing himself, cleaning up at each meal, putting his clothes away and possibly setting the table for dinner.
If he has good behavior or does chores tell him good job....etc...
Do not threaten to take his B-Day away over an over. Either take it away or not immediately. Consequences should be immediate. This is about his overall behavior that needs to be worked on.
Take him to a local pool, library, playground each day from 9 - 11 am.
Tell him after he clears his breakfast plate, you guys will be going to ____.
Tell him what u expect of him behavior wise. If he misbehaves there, take his hand, walk to the car, let him know in JUST 1 sentence why you are leaving and send him to his room. Hopefully, there is no TV, etc... in there.
Again w/out being there, I can't say too much, but, you need to have a structured routine ! And he needs to get some excercise and social time. He should be practicing reading, too. Go to the library, let him choose an age level book and have him read it to you -- where you need to be on the quiet side.
Good Luck and keep me posted !