Hi and welcome to the forum Sofia!
First question... You can't see the material textures in your plan view... but you can use "Bitmap fills/Tramas de Imagem" to apply real textures to your plan view... and save them as a regular dwg.
Second one... Try a search "3d Cutaway/Secções 3d"in the ArchiCAD Reference Manual... I think that will do the job.
Personally I'd render a"3d Cutaway/Secções 3d" top view of the building... Quick and easy!