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I was with my first Van by the time I was your age. I fixed it up for week end camp outs and day trips where I may sleep a few hours in the back of it while on the road if I got tired. That's how I got my feet wet. I had a Rand McNally Road Atlas (pre internet days back then) and a Camp Ground Atlas to find camping places. (very detailed book and helpful)
It will be much easier for you to get started here in 2017. At your age just a short Van in stock form would be all you would need. I'd suggest staying with a Ford or Chevy/GMC. This will likely have a V6 or V8 engine with an automatic transmission (Over Drive would be great if you are going to travel) They get better gas mileage.
You may find a retired Fleet delivery Van for a reasonable price and a lot of them will be white (like a refrigerator) which is a good color selection. Be careful of those which have signs painted on them as that may be difficult to
clean up.
You will likely find one with power steering, maybe power brakes. Nice things to look for: intermittent windshield wipers, AM/FM CD players with aux port so you can plug in a Cell for music or Mp3. A dome light in the back as well as the one overhead beside the driver. Tilt out rear windows. So you can open them on a warm day with front windows rolled down and get a breeze through the Van making it a lot more comfortable.
I have a lot more info below in my two websites. The first for converting a bare Van to a usable platform so it will have a bed in the back with storage room under it, and a kitchenette made from a discarded kitchen floor cabinet. You only need to put a plywood top on it so you can set up a cook stove and a sink. (the sink doesn't have to be plumbed for a drain...you can lift it out and dispose of the water outside in an appropriate area.
The second site is a Portal of handy information for planning a trip or to use while on one...say at camp planning your next day's journey....or while enroute looking for facilities like laundromats to clean dirty clothing. There are links to Work Camping sites too.
I highly recommend Bob's book. I had my local Library to buy a copy of it and it is getting a lot of circulation now.