Hmm, sounds like you got your first tricycle and you want to win the Tour de France.
One of the few things I learned when I wasn't selling insurance was K.I.S.S. keep it simple, stupid. Start easy. There are few builders who succeeded on their first models. A Sherman is a good start. Mostly one color paint job. Get the basics down first. Lay the paint on evenly, Get the decals to snug down, Fill the approporate seams. Make sure wheels and tracks are straight. Don't worry about advanced techniques yet. Learn to walk before you try to climb Everest.
Buy tools and paint as you go along. 200+ bottles of paint? Not a good move. First, your talking something like $600 or more. And many of these colors you won't need. For a closed up Sherman you'll need a WWII olive drab, very dark gray (for the rubber on the wheels and tracks if there's any), black (for the viewing ports) gun metal, silver (headlights), red (tail light) and clear gloss and flat. A decal solvent is good, too, Solvaset, MicroSol or MicroSet. You'll want a good cement...Tenax 7R is my choice. Don't bother with the tubes and get a technical pen like this as an applicator instead of the brush in the cap. It will last forever, is easy to cleanand provides extremely precise applications of cement to seams. Possibly a filler material, Squadron green or white, for example. Fine sand paper, sprue nippers, aka wire cutters, an X-acto handle with #11 blades. If you're brush painting, don't skimp on brushes. Lay out some dough for good ones. Sand paper, preferably wet and dry typs with some pretty fine grian. You'll get this at a hardware or automotive parts store. In fact, start by doing most of your tool shopping at the hardware store.
If you think you want an airbrush...wait. To get a good set up, you'll spend no less than $50 (Paasche H) and at least a hundred for a compressor. That's a lot of money to get into a hobby you don't know if you're going to like. Forget canned air and the under $20 starter airbrush. Save that cash towards the real thing.