Unable to answer "What kind of building is this?" for https://osm.org/way/139121209 via StreetComplete_ee 53.2:

This is a concrete ramp towards the house entry (vertical bar of the 'T'). It branches into 2 balconies (horizontal) bar of the 'T')

Attached photo(s):
https://westnordost.de/p/157842.jpg