I really don't think there are any specific magic numbers for that. We keep them in so many different conditions, in totally different climates, and manage them in so many different waysI don't think there is one specific number that covers us all. In your case, what age you process them enters into it.
I understand if you don't have any experience you need some guidelines. If you free range them, you really don't need much coop space, just enough room for them to roost. If they are locked in a coop all the time, they need a fair amount of room. There is a rule of thumb on this forum that has 4 square feet per bird in the coop along with 10 square feet per bird in the run. If they have access to the run most of the time they are awake that is probably more room than you need, provided you process them before say 20 weeks.
I really do hate giving hard and fast numbers. That may be way more than you need or it may get a little tight. There are so many variables it's not easy giving numbers.