I'm new to chickens myself, and we live in a cold climate so ours didn't even go out into their coop until they were 8 weeks. I'd let them out for a while during the day, and then for the 1st 2 weeks, it was a challenge getting them all in at night. It took about a week before they figured out the roost. We'd put a few up there now and then so the others could see what to do, but we let them figure it out. Now at night, they come in, eat and drinks and withing 20 minutes they are all on the roost.
Now they've been in their coop for 3 weeks or so and at night they just go in on their own when they are ready. We just keep an eye out to the coop when it's starting to get dark, and when we notice they're in we go lock the door. It's amazing how quickly they picked it up!