Food - you will want to feed them Flock Raiser their entire lives, with calcium free choice. They do better on this because they don't lay as many eggs (they are great layers until they go broody though) and the boys will not want any calcium.
If you plan on showing them you will want to make sure they don't break their foot feathers outside having fun. Some people keep their show birds inside on unscented unclumping kitty litter.
Sorry - no way to sex them at 2 weeks - or even at 2 months - probably closer to 6 months we can guess.
No in the house on kitty litter for mine, but I will watch those feathers! As for food-will I need to give them some other source of Calcium? I guess its a good thing I asked about food because right now I have them on medicated starter feed.