Get high quality lighting and materials

Hello!
Tell me please.

  1. Do I have to export each wall separately? To get a quality product at the output.
    I read that all the objects are advised to break up into 90 degrees
  2. Is there any way to import everything in one file?
  3. Every wall, door, window to import ?
  4. Which topic can be read at the forum on the topic - to organize the opening of the closing of doors. Interaction so to speak
    Sorry, I’m new! My English level is low =))

You don’t need to export each wall separately. All you need to do is make sure that the whole model is not a single object. For a better quality lighting, you need to break the Model into multiple objects. This is to avoid lighting artifacts and very high lightmap resolutions.

You can export all objects in a single fbx file.

Check the Unreal Wiki. It has lot of Blueprint tutorials including Automated door tutorial.
https://wiki.unrealengine.com/Category:Blueprint

Thank you so much !