Somebody tell me how i can be one?

i am 13 and i want to be a police dective you know like how those police on law and order and NCIS do. thats what i want. what do i have to do to be 1. i live in atl but whwen i go to college im goin to n.y so ima be nypd but what do i have to go thru to be 1. lie what school what degree oh yea ima a black female