Flying to America on my own when im 16... HELPP?

Right, my mum's said that when im 16 i can go and stay with family over there :D

So i'll have to get the plane on my own :o omg im scared:$

Like, i have no idea what so ever what happens at airports like when your leaving and when you arrive,

and how far can my mum come with me in the airport til im on my own?

cause im not an adult will one of the airport staff help me till i get on the plane?

whats the deal about luggage?

ive heard when u arrive u get asked questions by the airport staff.. like what?

when i arrive do i have to go through all the stages on my own or would i already have met my family by then?

omg im soo excited but proper freaking out like, i mean airports are busy places right...

ahhhh please help!?!?!!?!

thanksss