Chicken runs/coops would firstly need to be predator safe. I would use hardware cloth attached to a framework of your choosing. Check out hoop coops in Coops section for great ideas And answers to many of your questions.
Hi, I am a Long time lurker getting a great education here. I would say to get rid of the bread and parrot seed as treats, give some meal worms, cooked egg and fruit or vegs in small amounts. Chicks cant handle bread and bird seed. Maybe some electrolytes or even a tablespoon of Apple cider...