Hi, from the imagery we cannot see if buildings have shared sidewalls. So, when it is not clear that buildings are terraced (1 roof over the whole length)
we ought to map buildings as a single building, freestanding.
Most buildings are rather square.  A building with correct squared buildings is difficult to map, so each rectangular building need to be squared with the Q key while selected. (we are still waiting till it is possible to map a building with squared corners in 1 go in IdEditor, like in JOSM , another much used editor,)
You will find these agreements in the mapping guidelines. (best practice)
Here you find a video how to map buildings.
https://www.youtube.com/watch?v=U4Mfpnvp6Y8&list=PLb9506_-6FMHULD9iDUAh-4qpxKdVspnD&index=14

Best regards