Find out what food the breeder was feeding the kitten and stick with what the cat has been eating. If you must change foods, introduce the new kind a small amount at a time mixed with what its been use to. Cats can be finicky eaters but you can wean them away from the other food. Most cat foods provide a complete and balanced nutrition. You should vary the menu.
Cats eat to satisfy their energy needs.
Dry foods have more energy making elements than semi-moist or moist foods. Dry food should be left out for the cat if you work. One of the other two types should be fed to the cat once a day. Feed it as much as it can eat in twenty minutes. After the cat leaves the bowl remove it and throw the remaining food away.