Anything goes. Turn the pile occasionally and it will work faster. You can put meat in it, but that would probably attract pests (I don't for that reason - my dogs are the worst pests that way!)
I put in dog droppings and compostable cat litter. Weeds, leaves, lawn trimmings, kitchen waste. Water it regularly if you want, or if you can just leave it sitting and turn every so often, then it will compost more slowly but it will compost. I put a sprinkler on mine regularly in the summer to keep it working. I have three compost piles - the one I'm digging up to use now came from two years ago. The one I'm building this year is separate, and last year's pile is just sitting there, still breaking down.
The way to keep the dogs out of the kitchen scraps is to take out the kitchen scraps every time I scoop the droppings in the yard and commingle them in the pile. My yard is long and the neighbors aren't nearby, but still, I usually put it on top in the center and then scoop some of the weeds and grass in the pile over the top so it doesn't smell bad before it breaks down, in case anyone passes by.