Here's how you train chicks to go into the coop on their own.
I'm sure you've heard that darling trilling they do when they get in the mood to gather together to sleep for the night. Wait until you see them gravitating toward the coop and making that sound. If you don't know what it is, it sounds sort of like crickets chirping, very feint and soft.
Make sure you have a small flashlight or a nightlight to plug in near the pop hole entrance. You want to be inside the coop opposite the pop hole. Then you call to them. If you haven't taught them to come to you, then you need to teach them. It's easy. Just use treats and a verbal cue, the same one every time you treat them. They catch on very fast.
So you call to them, or show them some treats for just that first time to get them interested in coming inside. The purpose of the light is to show them what's inside because chicks are very hesitant to go anywhere they aren't familiar with.
It's important to not use any force. You want them to think this is a wonderful thing and it's their idea to go inside. For the first few nights I let them sleep anywhere they want, except the nest boxes. I usually block those off until they near point of lay.
The next night, repeat the process. Be patient. Let them come in at their own speed. I have one who always wants to be the last one in and she still needs to spend time going over every inch of the run before she's satisfied and decides she can go in now.
It can take as little as two nights for them to go in on their own, or as much as a week. But they usually catch on very fast. It's a very powerful instinct to want to get under cover before night falls.
After they go in on their own, then you can begin to perch train them. Simply place them on the perch near a wall if possible, and position them very close together. This is for reassurance, and it makes them feel more secure to be touching each other during this first strange exercise.
Roosting is also a powerful instinct, and you are simply capitalizing on it. They'll keep hopping off at first, but keep putting them back. Don't spend more than two minutes at it. Any longer is unproductive.
Lightly rest your hand on their backs and that usually calms them down and they're likely to remain if they calm down. This also takes only a few nights and they will be hopping up onto the perch all on their own. Mine were roosting at five weeks, so even very young chicks will learn to roost with a little patient training.
They won't need the light after they'll roosting on their own. If, for some reason, you have any that relapse and show reluctance to go into the coop, put the light back, and that should solve the problem. I use a little nightlight that plugs into a socket. Or if you have no electricity to the coop, a little battery camp light will work great.