If they are outside, they need to be protected from drafts, or have a warm and draft-free area to retreat to that is big enough for all chicks. It is most important for first couple of weeks.
Maybe bedroom first week or two, then outdoors with warm draft free area after that. If your chicks are shipped, I would go with indoors for a few days anyway bc of shipping stress and you can keep an eye on them for a bit before they go to an outside brooder.
When we have brooded chicks outside, we use an old dryer drum with a heat lamp inside. This is raised up on blocks, and they can get up on the blocks if they want. We then add another 2’ tall rectangular “box” around this to keep out drafts for a couple of weeks. They run Around in the cooler area and retreat under the heat lamp when they need it. There are no other chickens in the pen when we do this. This pen has a roof, but stiff wire fencing sides, so it is drafty and why we add the outer “box”.
We also utilized the old dog door in the barn wall - it leads to the chicken area. We built an in the barn brooder, with a chick door into the run. Heat lamp, feed and water are in the brooder, but, after about a week we open the chick door daily and they venture in/out of the run. We use a portable fence with some plastic garden mesh zip tied to it (to prevent the older hens from picking in the chicks). We use a variety of things to cover the top of the portable fence to provide shade and prevent hens from entering the area. The chicken run has a roof, so no problems with rain.
Good luck.
