Good questions, I'll add more details in tomorrow. But for the powers, they were born with the "gene" I guess you could say, but they start to develop later on. But yes, they were born with them. And as for the age of the officers, unless someone wants to play someone higher up and in charge, which is fine, the regular officers should be between 21-25. 
I'm going to add all of this and some more details when I have more time. Sorry for any confusion!