Dude. You have no idea how exciting that sounds! Well, maybe you do... and the fact that you're thinking about the smartest investment choice out therre at your age is even more exciting.
Rob Sasser is right, save some cash, (which will obviously not be hard to do, out on the ship!!) and listen to ALL the BP podcasts and read the blogs and forums. There is literally a college course, if not a degree in all that. there's over 140 hours of blogs, ALL fascinating, with exceptional guests, etc. And Josh and Brandon are so good about stopping these world class experts whenever they introduce even a slightly advanced term, and have them explain it for anyone who might not yet know the jargon. So download those before shipping off,, buy the book Rich Dad Poor Dad, and you'll have a ton of knowledge when you come back with cash in hand, ready to start getting wealthy!
what I, personally would do if I were you? is find your favorite place in the world (maybe best to start in the USA- though once you have mastered the skills, there are some SICK deals around the world that you might have easy access to abroad), if you can live anywhere and just report to your port of departure. I assume you'd like to have a home somewhere that you come back to. If that would be in a nice place where other people like to vacation, I'd find a great house and contact Vacation Rentals By Owner to see about having them manage and short term rent your house while you're gone. You could have a secure place in the house where you lock up your personal effects.
Your strategy could be to buy one of these in different climate zones, depending on what time of year you'll be home. Maybe one at Big Sky for skiiing, one in San Diego or a seaside place, one on Flathead lake!!, a condo in your favorite City! live like a rock star while your mortgage is getting paid by VRBO, and your housing is free, and in fact paying you a solid dividend with which to buy more properties. you get the idea.
The key to this, too, is that you, buying the property as your primary residence, can put little money down, so your return on your cash is astronomical! The rest of us have to put down 25% to 30% to buy investment properties, while you could easily do 5% to 10%...
In the place you want to start, interview a bunch of Realtors to find a hard working, honest person who REALLY knows the market, and more importantly, someone you feel really comfortable with. Depending on where you are, it may take a little time to find the right one. They can walk you through the process of Buying. That's easy. They can also send you to a few Lenders to interview and see who you like, who you want WORKING FOR YOU.
Depending on how much time you have when you're home, you could get into flipping houses as a way to build wealth. Good to have a mentor and have read up on it, but it can be fun and satisfying. Those properties you can either fix and flip or fix up and hold them long term.
Network network network. If your town has a Real Estate Investment Association, go there and meet everyone.
Good luck!