First, have him visit all of the services. It's a big decision to enlist and going into one office and saying, "This is for me!" is kind of a rush to judgment. All services have something different to offer regarding their roles in the protection of this country but they all have the same educational benefits and the same pay rates. Rates in the Coast Guard advance fairly fast, depending on which one it is. I can't really tell you what the Health Services (medical) rating is doing right now but like I said, ask around. I know there is a "C" school for radiology for corpsman if he so chooses to go that path. As far as "C" schools go, it takes approval from your command to go to them, depending on the demand and where he's at but I don't think he'll be getting into that right away. It's somewhat like a residency and he won't be a doctor per se. Any doctor will be an officer.
Enlistment bonuses kind of got lost there for a while when I joined. If that's something you or him are interested in, ASK. It's a long drawn out process, the recruiter should welcome any questions that you have and answer assertively.
Ask him why he wants to join, the real honest reason. It's okay to be selfish in the reasoning. Make sure it's what he really wants to do, if there is any doubt about it then he needs to step back and think about it again.
P.S. ROTC doesn't automatically make you an officer when you enlist, but it does make things go a little smoother with the military structure of it. You'll also possibly be able to enter at a higher rank and/or get a signing bonus.
