Sketch design 3

Here is what I have done weeks ago but it is just to catch up.
I used photoshop to fill my sketches. I didn't find the tool to paint the sketch so I only used photos to create my montage.
My feeling is that I need more experience on photoshop as it is my first year using it.

Quick sketch (5min)

photoshop montage

photoshop montage, much better with the windows (it look more realistic)

 I also couldn't find how to make the white background disappeared and used the sketches lines I have drawn (so I used the selection tool to incorporate the photos of texture and to make my line visible) But it doesn't look great. I need more work on that. This was done weeks ago (probably 4 weeks now).