Howdy guys, i'm new here.

My name is Scott, i'm 17 and a highschool senior. I've spent a few years in the BSA and have probally 50 or so nights of camping under my belt,but never truly been "backpacking". I've been hiking and camping, but never combined the two.

Over my christmas break i'm going with one of my buddies for a 20+ mile backpacking trip on parts of the AT. he gave me a general list, so i'd like to get yall's list too and see what all i need. I've contacted a user here with a kelty moraine 3600ci pack that i hope is still for sale. So that'll be my first pack if i can get my hands on it.
I've got a 0* mummy bag i've been using and in its compression sack its probally 9" in diamter and a foot in length. It may work to start with, but i think to become a true backpacker, i'll need a more compact one, so what are some ideas for that?

I've got my eye on some rain gear now, and i'll probally go cheep, like frogg toggs for my first set.
I've got a few fleeces to wear under it, including a north face

Where to go from there?
Socks, thermals, hat, light, and gloves..
then for when i need my on esental gear, as a stove and stuff, might as well get that list going too. but first , give me some ideas on my basics not including the actual camp gear (stove, tent,etc)