i'm new also only had my chickens since summer. The breed index will help you alot in the choosing. As far as how many that depends how big your coup is. But if it helps build the coup bigger then you think you'll need. That way you'll have room to add more later on. just my 2 cents.
hi and welcome! I'm new too, I've been researching alot about breeds. You have to decide what's the most important to you, eggs, meat, appearance, temperament, etc. Also, if you have any limitations as to how many you can have. Good luck!
HOw many birds you have is very subjective. THe more birds, the more space required. A bigger coop, or many smaller coops; and more pen space. Or if you intend to free range.
I started a year ago by picking what I thought were birds that find my specific needs: egg production, free range ability with thought to predators and color to hide from predators; and keeping to the 25 count in a box. I now have many more, maybe 100 birds including ducks and turkeys too. I have kept to the dual purpose types and mostly from the hatcheries which are much smaller birds than the heritage lines.
For easy temperaments stick to the traditional dual purpose types and most egg layers. RIR roosters can be a bother. ( My boys carry a stick at all times.) But he is also one to defend the flock. I skipped the Faveralle because they apparently are very docile and I didn't think they could withstand the RIR.
Consider the RIR as this bird started in RHode Island; southern New England is cold and rainy maybe much like your area. Some feather types do better in the rains and the winds. Some birds are very fluffy like BO and others are tighter feathering; I've been watching my birds to see if this makes a difference. Windy rainy weather is their least favorite weather. I would look for breeds that can handle that climate.
Perhaps you can check with your state threads and ask what breeds anyone there has and why.
Be prepared to deal with a rooster; the hatcheries are good at sexing but not perfect.