Unable to answer "What kind of building is this?" for https://osm.org/way/355079086 via StreetComplete 55.1:

This is a tent

Attached photo(s):
https://westnordost.de/p/187983.jpg

The place has gone or never existed. A user of Organic Maps application has reported that the POI was visible on the map (see snapshot date below), but was not found on the ground.
OSM snapshot date: 2023-03-29T15:44:03Z
POI name: Aéroport International de Yaoundé-Nsimalen
POI types: shop-travel_agency
#organicmaps