HALO 4 Anyone (Help)

So the RTX convention that I attended with my son was primarily HALO, so he has asked that I start playing it to join in on some of the game nights that they host.  I really have no clue and would like any help that anyone could offer.

He was showing me some stuff yesterday.  Of course, I was totally lost and not sure what was/are the best loadouts to work for or any type of strategy for map control.  Definitely a NOOB!!!

HELP PLEASE!!!!

I won't be on tonight but should be playing tomorrow night if you want to help.  8or9 central to 12.

Thanks in advance!

Help anyone????