1. Only necessity is a weapon and a way to dress the animal. I have camo for bow season but once it gets cold out I usually just wear my brown carharts with no trouble. You may also want to invest in a treestand.
2. Why on earth would you take a heater to the woods with you. If you dont like the cold you shouldn't be deer hunting IMO
3. Field dressing a deer is very simple, there are many how to videos out there to help you out.
4. As far as meat it just depends on the size of the deer. From my deer last year that dressed aprox 120lbs after processing I ended up with 4 Roasts, backstraps and aprox 30lbs of burger, give or take a few lbs (can't remember exact amount)