Baby broilers and baby pullets together
One year I had a moment of weakness and got 6 layers with my broilers and put them all in the brooder together. You can do this without issue really, for a few days, but you'll have to separate them out after about 5 days because your broilers will be about double the size at that point. In addition, meat birds eat all the food and drink all the water and are really stinky and dirty. Your layers won't get anything to eat or drink and won't be happy.
Your layers will stay in the brooder until they are fuller feathered, unless you have a large number, while your broilers will go in the tractor at about 3-4 weeks.
Here's what we do. We have a commercial brooder / lights like they have at TSC and bucket feeders/waterers .This is our 5th year with layers and meats:
15 layers go into the brooder for 3 weeks. Transfer to a 2x4x8 indoor mess bottom tractor until they are 7 weeks old. Then transfer to an outdoor coop attached to our chicken coop - it's our "meet and greet" coop so they can get acquainted with our flock without getting beaten up. They'll get integrated at about 15 weeks.
30 meat birds go directly into indoor mess bottom tractor until 4 weeks old. Then separated into two outdoor 2x4x8 outdoor bottomless tractors in a 40x40 electric fence. We process at 9 weeks.