Hens that go broody have varying degrees of skills & abilities. That's why one approach won't fit every sitution. Some hens are more easily distracted & disturbed and must stay confined, others could successfully hatch a clutch in the middle of Grand Central Station. Some hens are more protective and could keep her chicks safe while walking through a den of foxes. Others will kill even their own chicks.
I have about a dozen mixed-breed bantam hens who go broody on a regular basis. I let them get settled on their selected nest site and give them some bantam eggs to satisfy them. After a few days of this I'll move them after dark to a separate secure place. I have a collection of wire dog crates & wire tops to rabbit cages I can use. I put the cages in a separate pen I keep for chicks & broodies. If they stick on the nest in the new place for a few more days, I'll then swap out the bantam eggs for other eggs from my standard-sized layer flock. I don't want to make any more bantams, especially bantam roosters!
I keep food & water in the cages, & there they have room to get up & poop. I shovel out & toss their broody poops so it doesn't get too rank in there. I don't like to bother them by candling the eggs, and don't force them to get up off the nest to eat or poop.
Once the chicks hatch they & their Moms can stay in the pen, and sleep secure in the broody cages. The Moms will want to stay with the chicks for anywhere from 4-8 weeks, more or less. They can easily hop over the fence to rejoin their flock when they're ready to leave. I keep the chicks together, separate from the flock, until they're 20 weeks old and can begin eating layer pellets. Until then they stay together & eat chick starter.