There are various approaches you can take, but just be aware that each has its pros and cons. My preference is to separate the broody in view of the rest of the flock while she's incubating and for the 1st week after the chicks hatch. Then I remove the barrier and let her move at will between her broody area and the main coop, so she has a choice of how and when to integrate her chicks with the rest of the flock. I partition off a small (3 x 3 foot) area of the coop with chicken wire or hardware cloth. The barrier is generally about 6 feet high to keep her in and other flock members out.
One of the biggest pros to this approach is that other hens will not be moving in and out of the broody's nest box. The risks of allowing other hens to have access to the broody's nest box include: 1) other hens will add their eggs to the ones she's incubating, which means you need to mark the original eggs and you have to disturb the broody daily to remove eggs that shouldn't be under her; 2) the added hen traffic in the broody's nest box greatly increases the risk of ending up with broken eggs, which can ruin the whole batch; and 3) when the broody gets off the nest to eat, drink, and poo she may return to a different nest box, which means the eggs may cool down and die.
The downside is that she'll probably go broody in a nest box in the main coop, and then you'd have to move her. This can break her broodiness, but I've never had that happen. I leave her in the nest box in which she's gone broody for 2 or 3 days, then move her at night onto a nest of fake eggs in the new location. For at least the 1st week, I put up a visual barrier (e.g., an old bedsheet) so she can't see outside the new broody area. If she remains broody in the new location for 2 days, I switch out the fake eggs with the eggs I want her to hatch.
After the chicks hatch, there's a 5 to 7-day period when the rest of the flock can see the broody and her chicks but not bother them. This gives the chicks some time to gain strength and speed, and learn to listen to and follow the hen before they directly encounter other flock members. I've only had mid- to upper-ranking hens go broody, so I've had no issues with either the hen or her chicks re-integrating with the flock, even when the flock did not see the broody hen during the incubation period.