You may have already decided this, but one quetion is whether you isolate the broody and chicks from the rest of the flock. Although this link is tilted to my way of thinking, it does give some considerations and other people's opinions. It might help you. To me, how much room mama has to work is the prime consideration in this decision.
Raise with flock? thread
https://www.backyardchickens.com/forum/viewtopic.php?id=215937&p=1
If you do isolate the hen and chicks, make sure the fence is secure so the chicks cannot squeeze through and get away from mama's protection. If the chicks get in with the rest of the flock without mama being able to protect them, the other hens will probably kill the chicks.
If you isolate them, mama will do well on chick starter. She does not need the extra calcium as she is not laying eggs.
If you do raise them with the flock, I'd suggest making a secure space for the chicks to eat and drink that the others cannot get to. A milk crate, a box built out of slats, whatever, that can be set over the food and a shallow water dish that the grown chickens cannot get to. Openings about 2-1/2" seem a good size as long as the food is far enough away so that the hens cannot reach through and get to the food. I'm not suggesting this for the chicks protection fromthe other hens. A good mama will take care of that. It is just to give a place you can feed the starter without the other hens getting to it and give the chicks a water source low enough for them to get ot without the bigger chickens messing it up.
Regardless of whether you isolate them from the flock or not, you do not need to provide heat. That is mama's job. Her heater never runs out of fuel and is never disrupted by power failure.
Good luck!!! Exciting isn't it?