No matter what.
Proto SLG or Invert Mini
68 inch (or smaller if you which) 4500 PSI carbon fibre tank
Rotor or Prophecy.. i know its pricey to start off , but its better in the long run. However it is acceptable to buy a halo reloader/ invert too these are a little bigger and worse however i started with one, and they work just fine...
Your mask really makes a difference. I would recommend the Dye i3 pro's or The Proto axis' Both of these are basically the same, but hte proto is newer so is a little better. Either of those will give you a solid base on what kind of mask you would like, or stick with those. For example if you dont like them, which is unlikely, jsut tell someone what you dont like about it. for example too heavy and people will tell you what to buy to change that.
For Kit, depending on where you think you will be playing dress accordingly, For example on hte speedball pitch you can just go nuts with your colours as its not really worth wearing red and blue jsut to fit in
But in the woods it can be worth it to go the extra mile and go with some form of camo, for example the planet eclipse camo gear, or the Dye camo gear.
If you buy all that, and turn up at a walk on or training day, you wil fit in like a paintball in a hopper.
Keep in mind, paintball is pricey and dont feel bad getting stuff second hand. All of my gear is second hand, and its still all working