Add me on xbox live???????!!?

well i have a few questions for you? do i have to change my gamertag? and do u only do sniping or can you still use a full auto, and what are the tryout rules, if you think i could make it check out my YT channel at www.youtube.com/user/THEdustymonkey100 and you can message me on there just tell me i met u on here, i do like to snipe just not all the time so it just depends on what your looking for