I went into the Navy at 19. I did not pursue B.U.D.S. until I was in for 3 years and became a S.A.R. swimmer which was pretty damn intense as it was. Nothing wrong with dreaming, at his age he can prep himself when he has time, he may get in the Navy and hate it, many do, I loved it and miss it.
I screwed up and beat the living out of a 1st Class Radioman who slept with my girlfriend that I flew down from Michigan. He lost his Top Secret clearance, I lost my secret clearance and the skipper was pissed because he had two really over qualified janitors on his hands and he took it out on me, oh did I admit that I was drunk when it went down, they wanted to send me to ARC(alcohol rehab) for 30 days, at first I agreed but after being busted in rank, losing half months pay for 2 months 45 days of restriction and extra duty and losing my billet to B.U.D.S. (was supposed to go 6 weeks after this incident took place) my dreams and vision changed and I refused to go to ARC and they sent me home with a General discharge. End of story.