As soon as
Tractor Supply announces "Chick Days", my wife gets the fever. Although we love watching a momma hen hatch out and brood her own babies, that's too long a process and too few chicks for her. She wants lots of chicks, right now. So in 2016 we had to purchase 35 in one week. This past year we bought 31 in one day.
We have a brooder set up on our back porch. Springtime temperatures here are mild enough that by week 3 we usually don't need a heat lamp except at night. We don't have electricity run to our coop, but prefer to have easy 24 hour access to the baby chicks to respond to any problems in the brooder immediately. Plus they end up much friendly than coop raised chicks.
All our chickens free range all day and come up on our porch frequently looking for treats or petting. So the babies see and here them all day long. Our main rooster will perch on the railing near the brooder and crow at them in the mornings and the hens hop up to check them out all day long.
We keep them in the brooder for at least 4 weeks, until they get some decent size and feathering. Then I move them to a segregation pen in the main coop. It is a 6'x8' chain link dog kennel that I assemble and disassemble when needed. Fortunately I built our coop big enough that it has plenty of room. They are locked in there for a week or so, giving everybody time to get used to each other but not have physical contact. I transfer everything that was in the brooder to this pen. Bedding, feeders, perchs, everything. Whatever they have had for the first month goes out in the pen with them so they aren't surrounded by all new stuff.
After the first week, I raise the pen walls up high enough that the chicks can crawl out under the fence, but the big chickens can't get in. This way they can explore the coop and run, but quickly seek shelter back in the pen if one of the adults goes after them.
I use either blocks of wood or bricks to get the fencing up about 4" off the ground at first. Then as much as needed each week until they are 8 weeks old. At 2 months I take the pen back apart and put it back in storage until needed again. It only takes a few minutes and isn't very heavy when broken down in to components. Within a week, they all end up following the bigger birds up on the roosts to sleep at night.