They won't start laying until they have been finished with 'mothering' for at least a few weeks. It takes time for those hormones to clear their systems.
He won't be the dominant one right away. He's brand new to the flock and has to earn the top spot. That will take time, and can only happen if he is in the flock. You need to let them work the pecking order out. It may seem rough, but as long as he isn't injured to the point of bleeding, leave...
Just give them time. As long as you have multiple feeders available and he isn't actually getting hurt, it will be fine. He's young right now, and all the chasing and pecking is part of establishing pecking order. It's just what chickens do when you add a new one to flock. It will pass. And once...
It's molting season. Some hens molt very hard, others have a barely noticeable molt. It's very normal for production to slow down prior to the molt. So even if you don't think they are all molting yet, they may be starting to very soon. Layer pellets are for actively laying hens only, so you may...