They need to have chicken feed appropriate for their age...Layer after 18 weeks, starter/grower before then. Free ranging will allow them to eat greens, bugs, etc which they love. They need grit to help break it down. Most grit can be found if they have rocky soil to peck around in. I free range, but also offer grit to help them out. Calcium (oyster shell) is not grit, but is good to off them once they begin laying. This will help their eggs to form nice hard shells. Scratch is a mixture of seeds and grain that the birds enjoy, but is not needed for a healthy diet...the chicken feed gives them the balanced diet. But you can offer scratch as a treat (I throw some in the run when they have to be cooped up for the day). Good luck!