Your chickens will not wander and roam at night. Chickens go to roost at dark. They seek high close spaces for their own protection. Chickens go into a hynotic kind of sleep at night.
They need to be locked in their house at night for their own protection. Predators love a good chicken dinner. If you leave your hen house open they come back every night until you no longer have any chickens.
I would suggest limited supervised roaming of your yard. they will eat and scratch up everything you don't ant them too. They will eat your flowers, gardens, and other plants unil the dirt is bare.
Build them a secure run. Shut them in their house at night. You should have chickens that live a very long life.
Let them range, leave them unprotected and you will have many many creatures roaming toward the scent of chickens that will feast on your birds until they are all gone.
Keep food and water available at all times. Especially since it is summer they need lots of fresh cool water daily. If they don't have enough feed available they will begin to pick and peck each other. They will start feather eating too. They will pick another chicken until they are a bloody mess. If they are hungry and don't have enough food available they will also eat their own eggs.
Save yourself some worries. Lock them in at night. give them a secure run int he day. Keep feed and water available at all times.