All the things you should buy [and more!] when they are chickens you should buy,
Chicken wire [to go over the box]
Marbles to go in the water
Food holder [the ones with the covers work best]
The one with the cover is good because they may poop in it and make a mess.
Here is a list that is all the things they need when they are pullets and older
Large water holder
You will need to make sure that you get bigger water and food holders because it your chickens get bigger and older. You put marbles in the water when they are chickens because they may drown if it is to deep.