Unable to answer "What kind of parking is this?" – Parking Lot – osm.org/way/1281786355 via StreetComplete 61.2:

I think this polygon isn't parking, but the area next to it is. Photo is taken from across Bowker Street, with One Congress behind the camera to the right.

Attached photo(s):
https://streetcomplete.app/p/296435.jpg

Unable to answer "What is the width of the opening here?" – Gate – osm.org/node/631509370 via StreetComplete 61.2:

It's about 10' 11" curb to curb, and about 5' 2" curb to pole (on either side). Though, I'm guessing that this entrance normally remains locked.

Attached photo(s):
https://streetcomplete.app/p/296423.jpg

In context of overlay "Surfaces" – Driveway – osm.org/way/8615296 via StreetComplete 61.2:

Not a driveway, but a walkway.

Attached photo(s):
https://streetcomplete.app/p/295856.jpg

In context of overlay "Things" – City of Cambridge (Recycling Bin) – osm.org/node/13048765935 via StreetComplete 61.2:

Accepts: clothing, footwear (in pairs), accessories, linens, etc. Must be dry and odorless.

Attached photo(s):
https://streetcomplete.app/p/295843.jpg

Road direction is north. Several roads in this area have traffic going the wrong way on the map.