Parrots have very high energy requirements, more than any other pet. Moreover, they need different kinds of vitamins and minerals in order to stay healthy and happy. Therefore, they need to be fed with a balanced Parrot diet. For you parrot not to starve, you should offer him the same diet which is available in the pet store. You can research different brands, but the best way to do it is to see what other parrot owners are feeding their pets, and then buy the same product. You can also buy a raw diet, but as it may be more costly, it may not be such a good option.