properly oriented?
In blender, select your mesh, go to edit mode, and press "n". In the sidebar that has opened up, under the "Mesh Display" tab there are two toggles under the word "Normals". Click the one on the right which is a cube with a face selected. The lines that you see on your mesh are "normal lines" and they designate which side of the face "faces outward", and therefore which side proper shading should be applied to. If any of the normal lines are on the faces that are messed up in the pictures you supplied, then you have normal issues and can either manually flip the normals, or fix them by selecting your entire mesh and pressing "ctrl n", which recalculates the normals. That usually works, but if not, go back and fix remaining normals. If all of your normals are fine, then another issue could be that your transparent faces (windows) should be a separate object from the other faces.
