lol no need for that
OP, get av'd and buy from this site, if you aren't 18, then don't buy anything until you are.
Next time, try using the search function, "what first gun should i get?" is hardly an original or well-thought out question and will get you burned quickly here.
Yes a pistol can be used as a primary, especially in a cqb environment, outdoors you might be outranged and unless you have a pile of mags, you will need to pick your shots