There is a mountain behind my house, and the old house less than one meter in front is three or four steps higher. Is there any way to solve it?

Nothing. You want to ask about Feng Shui. Is there an anterior chamber blockage in Houshan? Mountain shade, room shade. Only Gao Heyang. You have the conditions to build the house to the height where you think solar energy can illuminate all rooms. There's a house ahead, so you have to return from the main room. You can return as much as you can, which is convenient for you to get in and out. The house can be ventilated and light for a long time. But remember, the door should not be in someone else's corner or cornice.