My 07 ford F 150 all of a sudden will not start.

It dosent mean you have a good battery just because its NEW but saying it is and then your Alternator isent putting out its power which at idle it should run at 13.5 volts and charge the battery by just sitting there ,,so turn on the Head lights and if the battery is good the lights will be bright if not then the battery is down so jump start and with lights on Take off 1end of black (earth)lead and the lights should stay on bright,,if not then the alternator is no good ,get a reco one or changeover and refit it and try again.
The alternator also has a feed wire going to it from the battery so make sure you have power to it before taking it off,, or even before starting work on it .
Let me know how you get on .. Ron

I would have the battery tested, and the alternator might be junk since the truck woln't stay running once you remove the jumper cables.