Hi Ricard with an H - thank you for making the pic smaller.
Yes, the side compartments are nest boxes - dark and cosy and filled with shavings or horse bedding - something soft. They don't need ventilation in the actual nest box ....hens like dark secret places to lay their eggs. The lid lifts up so I can collect the eggs. There's also a foxproof lock on it.
The actual henhouse roof also lifts off for ease of cleaning. As it's all made of wood, before we painted the outside I liberally painted the inside with Creocote (like creosote) to prevent red mite. Will repeat once a year.
There is a perch inside, placed higher than the nest box. Hens like to roost high up and hopefully will sleep on the perch rather than snuggle into the nest box I put a layer of newspaper on the floor, under the perch, to catch the droppings. There's also a layer of bedding on the floor. Just roll it all up every few days and replace with fresh.
There are many different styles of henhouses now - plastic and wood ...ease of cleaning and being predator proof is a big consideration.
They have layers pellets, a separate bowl of mixed grit and clean water daily. Plus a few greens from my veg plot. They also tootle around in the garden looking for worms and bugs and digging themselves a dustbath when I let them out (when I'm around to keep an eye out for urban foxes) but I protect my precious plants with a little fence and my pekins can only jump up about 18" high and don't fly at all. (well, only with the wind behind them). Hens need worming with Flubenvet once or twice a year and protecting from red mite by a liberal dusting of the appropriate red mite powder.
It's great fun looking after hens...their needs are quite simple really. Safety, shelter, food, clean water and a willing servant (you)