Welcome to BYC!
There are lots of options - where are you located? (this will play into what may or may not be readily available to you). For laying birds you can opt for layer ration (comes in pellet, crumble and mash form) or you can feed them a grower type ration (same feed you feed young birds/chicks) and offer oyster shell on the side to provide the calcium they need to supply the shell for their eggs. Beyond these types of feed you get into the many, many, many brands that are out there. I would suggest visiting a couple of feed suppliers that are convenient to your location and see what brands they stock on a regular basis - this will give you a starting point for choosing which specific feed you want to buy. There are organic/non-GMO feeds if that is something you want to worry about. The "best" feed for you and your birds is going to be the one that is easily obtainable, is in the price range you can afford and fits what *you* want in a feed program for your birds.