buy a microsoft membership card at mostly any department store and type it in on your xbox (or you could type in your credit card information). Or sign up at Xbox.com
If you are asking how to connect to the internet then you have to buy a wireless router, hook it up to your computer and sync it with your xbox. You sync it with your xbox by going into settings and just following the instructions.
buying a new card for xbox live
Yes, you can use your Xbox Live account on your new Xbox One.
Xbox live is the online program included in all XBox. So yes.
download them from the marketplace on xbox live
No, Kinect works without Xbox live. If you have Live then great. Kinect adds a couple of new features to Live.
If you have a Xbox live Gamer profile, you can just recover it on the new Xbox. If you are not online, you will need to buy a transfer cable.
No
Yes
If it's in your XBOX, you have to buy xbox live then put in the code on your xbox, and you can play live for mw2.
Yes you have to pay money for another xbox live account but you have a one month free trial with a new gamertag.
Yes. but you can get banned from xbox live if m$ detects it
NO you can also use wired