Not sure exactly what you are asking, but i'll try.
You start out feeding day old chicks starter feed, all they want and can eat, and sugar water for the first few days to give them an extra boost. After about a week, you can give them plain water.
After 4 weeks, you can either continue the starter or switch to a starter/grower.
After 8 weeks, you switch to a grower formula til they turn 18 weeks.
After that, you feed layer feed.
The difference is the amount of protein in each type. The older they get, the less protein they need. Usually starter feed has 20-24% protein, whereas, layer feed only has 15-16% protein.
I'm not sure exactly what you feed roosters. I feed mine layer, bacause you can't separate them.
I hope this helps, sorry if you meant something else.