What kind of armor?

So many armors, what kind is best for a beginner? I'm 5'7" about 210 lbs (but losing weight).

Nothing accurate at the moment unfortunately.

Try RT Mod.

RT mod on someone 5'7 will look silly - rt mod is designed for troopers well over 6 feet tall and well built with it. Try any of the accurate cast from - AP, ATA or TM. Start as you mean to go on.

With the few extra pounds it's going to be difficult getting into anything like AP or ATA. Both are great for the shorter trooper but would probably need a lot of shimming. It's all possible but heavy shimming can look a bit naff.
TM is a more viable option. The chest and abdomen pieces are naturally more generous (being closer to the genuine sizes of ANH suits and not recast from shrunken ROTJ parts) and there is quite a lot of allowance in the limb pieces to be able to leave them with a good deal more girth.

A friend of mine is close to your size, being around 5'10" or so, and about 200 lbs, and his TM fits him like a glove.

I was under the impression that RT Mod was for the wider chaps as well... sorry.