/diy/ - Do It Yourself

hey /diy/, long time no see since i haven't had the time or ability to lurk here for a while.

i would like some practical help from you guys concerning backpacking.

i want to start backpacking/camping in my area. i have hiked/hunted it all year, and now i want to overnight there. i received a nice, large framepack for Xmas, and now i need to know what to put in it for, lets say, a 3day/2night trip.
i have good clothing, but i basic camp utensils and knowledge. for example,
-it gets about 15-20*F here at night minus windchill, do i need a tent? if so, good, light tent recommendations?
-i have a surplus down sleeping bag, will this keep me warm enough, or do i need a source of heat like a lantern?

can you guys help me out?