Hello there and welcome to BYC!
First, you might want to start with some reading in our learning center. Lots of good articles on getting started, building the coop, raising the chicks and keeping your adult flock happy, healthy and safe from predators...
https://www.backyardchickens.com/atype/1/Learning_Center
As for breeds....there are lots of hardy, docile, and great laying chickens out there....Buff Orpingtons, Barred Rocks, Australorps, Wyandottes, Sussex's, Rhode Island Reds, Easter Eggers, etc... You might want to take a look at these two breeds pages on some quick info on the different breeds and their attributes....
http://www.sagehenfarmlodi.com/chooks/chooks.html
http://www.albc-usa.org/documents/chickenbreedcomparison.pdf
As for adding heat to the coop....Chickens can adapt to the most brutal of cold temps. There are members here in Alaska that keep their chickens in un insulated un heated coops. I do not use heat unless it is going to be -30 or more at night. If you build your coop with plenty of venting in the roof, have them roost low to the floor in quiet air, and they stay dry, they can tolerate some very cold temps. Chickens need to be able to go out side during the winter, not locked up in a stuffy bad air coop. Keep the air moving at the eaves of your coop to bring in fresh air and let out the moist wet air from the breathing and the pooping, and your birds should rarely if ever need added heat.
You also might want to chat with your chicken neighbors in your state thread to see how they do things in your territory...
https://www.backyardchickens.com/t/440277/the-middle-tennessee-thread
Most dogs see chickens as dinner. So if you keep a dog on the loose, you will probably have to keep the birds in a run. There are threads here on training the dog to not eat your chickens, but not all dogs respond to these techniques...
https://www.backyardchickens.com/t/700017/how-to-train-your-dog-not-to-kill-chickens
Good luck on this new adventure! If you have any further questions, feel free to ask. Welcome to our flock!