Food should be removed from the coop area at night so it doesn’t attract critters. Water can start but should not be inside the henhouse. Btw the henhouse is usually called the coop and the outdoor fenced in area is called the run. So keep the water in the run. Water, indeed all sources of moisture, inside the coop can build up condensation in there and on the chickens. In winter this is the reason for frostbite. Other sources of moisture in the coop are the respiration’s of each bird, and their poop. Adding a heat source can actually make it worse with cold air hitting heat and moisture. The answer isn’t heat, it’s ventilation.
Of course your question was about them going in at night. So back to that. I agree you shouldn’t use the auto door till they are consistent. And the light outside should be off so they face low the natural seasonal light patterns. Sudden light and sudden dark is frightening and confusing to them. As it gets gradually dark they want to go to their safe place. The most common way to teach them where their safe place is, is to lock them inside the coop with food and water (one of the rare times to put food and water inside) and don’t let them out for like a week. They get real familiar with the space and begin to feel comfortable there. They start to recognize it as home.
As for chickens needing 14 hours of light, this is true but seasonal. Are your birds laying eggs yet? Chickens get natural light for extended time in the spring and summer. This stimulates them to lay eggs. As days get shorter they get less light and slow down egg production. Some even stop. It picks up again as days get long again. You do not need to supply them with artificial light unless you are needing them to lay consistently in all seasons. Perhaps you sell lots of eggs so you need that to happen. One thing to remember is their bodies have a set lifetime number of eggs. By making conditions to lay all year long they finish laying much younger in life. So it’s a personal choice depending on what you need from them. I don’t use lights myself. I can wait a bit for spring. I don’t try to make a living selling eggs. They’re just for the family and a few friends.
Geez I do ramble don’t I? You could help us give you more precise advice by posting a few photos of your coop setup, inside as well as outside. The run too. Do you have it critter proofed with hardware cloth? What kind of ventilation does your coop have? Where are you located? Texas chickens have different needs than Ontario Canada chickens.
This site has taught me sooo much. You are in a good place here to learn the best practices. Once you know what to do it becomes easy and you can enjoy your birdie babies. WELCOME TO BYC!