On Google Maps, for example, I select a section of the territory, and then Unreal Engine 4 accesses some libraries and takes the heightmap for that section from there. The game engine applies this heightmap to the landscape it has just created . This way, the landscape is loaded with the heightmap on it. After a few operations, the operator closes the landscape and its further fate is unimportant (it can be deleted).
Therefore, first, I need to learn how to create a landscape and apply heightmap to it through a button or code.
The short answer to your question is: I need to create a landscape with a heightmap and then it will be unchanged .