The best way to raise organic healthy chicks is letting their mother feed them. Beyond this, if you have purchased babies then you have to replicate what their mother does. In this instance, I would recommend you buy commercial chick food so they get the best start and then let them raise their own broods.
Get your babies some chick/turkey food at about 20% protein, that will get them across the line but you also have to take them out onto some clean dirt/lawn and let them play and pick and run around you. Share a bit of bread or something like that with them. This is a great time to train them.
Understand we know that milk formula is not replacement for mother's milk for our babies but it works just fine when mums' cannot feed them for whatever reason. Your chicks are in the same boat. Fed them well but also enjoy them and by taking them out and playing with them, you will be doing them wonders.
Chicks are inveterate pickers, they pick at things incessantly. Give them access to clean soil and scratch it with your fingers and call them by saying 'chook chook chook'.. They will respond, it is fun.
Meghan, in australia we call chickens 'chooks', and I have raised a lot over the past few decades to the point that if I scratch the ground and say 'chook chook chook', a mum with a dozen chicks will run up to see what I have found.
mike, Katherine NT in the hot dry tropical savannah bit of Australia.