Welcome to BYC. If it's non-medicated, you can continue to feed it as a grower until they are 16-18 weeks, at which point you can switch to a layer feed. Regular medicated feed should be switched to non-med grower at 8 weeks. Please note that medicated chick starter is recommended. It's probably not going to hurt them to be on a non-med but medicated gives them a better start.
Welcome to BYC. Glad you decided to join our flock. X2 on QueenMisha's advice. If you haven't done so already, definitely check out our Learning Center at https://www.backyardchickens.com/atype/1/Learning_Center. There is some useful information there in our coop section. Please feel free to ask any questions you may have. We are here to help in any way we can. Cheers.
I am one to stop the medicated feed early. I find that they get diarrhea pretty bad with it..tried different brands, still get the runs. Hmm, not sure if this is happening to others. I go to reg. chick feed after them being on it for two weeks. I've had healthy birds. No problems.
Welcome to BYC and the coop! There's a lot of great peeps here! Feel free to ask lots of questions. But most of all, make yourself at home. I'm so glad you decided to joined the BYC family. I look forward to seeing you around BYC.