If the rooster and hens were together when you got them, it is best to keep them together. Chickens have what is called a pecking order. It is common in nature with animals that live together, such as wolves in packs or cattle in herds. It is not that there is one dominant animal and all others are subservient to that dominant one. Every animal in the flock, pack, or herd knows its place socially. They all either rank higher or lower than all the others. That way they know who gets the privileges of rank without having to fight about it all the time. However, determining that position initially does involve fighting or pecking and can be quite violent, sometimes even deadly. If they have been living together, that is already worked out, but if you keep them apart long enough for them to forget where they rank, the pecking order will have to be reestablished. It is usually less complicated when it is a rooster being introduced to a flock of hens if the rooster is at least as old as the hens or fully grown, but there can still be violence.
Broody is when the hen gets an attack of hormones and decides to raise a family. Different hens exhibit it differently, but in general she spends almost all her time sitting on the nest, whether there are eggs in there or not, and she gets extremely defensive about her nest. There is no guarantee that any of your hens will ever go broody. Some do regularly but many have had the broodiness bred out of them. They either will or will not go broody whether there is a rooster with them or not. Doesn't matter.
Good luck!
