Welcome to BYC! The best way to keep chickens in the garden is to build chunnels (chicken tunnels) through the garden. Chickens aren't good with boundaries.
Welcome to BYC, Lisa. I'd make Mr. Red a seperate space/ home within the flock. He will get better with age. Like humans, the male takes a little longer to mature. His hormones are raging but he will get better with time.
Its really hard to keep any pasties around here. I don't know where they go 🤷♀️🤣 but I'm pretty sure the doctor would figure it out when I set foot on that nasty scale.