Data in Urban Area
Do you have any recommendation where to get data for urban area that can classification between building/roof,
or have you know any project that using data similar like this?
There are loads of projects like this. The topic is called "building segmentation" or "object detection" with satellite images.
Please have a look at this link: https://github.com/chrieke/awesome-satellite-imagery-datasets
Furthermore, it is even possible to make some tryouts with sentinel2 imagery.
As it is a quite complex topic, you could start to make some segmentation try-outs with the Orfeo-Toolbox Plug-in in QGIS.
Here a pre-processed datasets showing all urban areas world wide: