My Character Cannot Move In A Room/Spawns Outside

Hello,
My character cannot move inside the room when i enable auto collision. That is expected. So In Blender I tried to build UCX collision boxes that covers all the walls, floors and every detail. But it takes forever since my overall house model is too large and too detailed. I tried to import the room fbx file as seperate objects(Wall,Floor etc…) and it did not work either. What can I do in order to make the character move and collide with walls, pass through doors etc…?

Thank you for your interest.