The tea houses provide lodging and meal facilities. They provide a twin bedroom with a pillow and a fuzzy blanket. You will have to share a shared bathroom with fellow trekkers. The toilets are generally of squat style.
Besides that, you will get all the meal facilities in the tea houses as well. You can get all the meals of the day i.e. breakfast, lunch, and dinner in the tea houses. The food might not be fancy but provides you with excellent nutrition and adequate energy for the trek.