Basically just make sure that of the food you offer 50% of it is protein. As for how much to feed, all I did was put alot of food in there and if they didn't eat it all put less the next night until you get to a point where only a little is left. Make sure to leave a dry food in there 24/7 incase they get hungry during the day.
A tent is just like the ones you go camping with. You can find a good sized one at Wal-Mart for about 15$ in the camping supplies and hunting section.