I'm working on some Dutch records right now and I think I have this right, but i'd like a check.
The website WieWasWie has indexed much of the digitized records held throughout the country. The actual digitized records are held in regional archives. The search pattern is go to WieWasWie, enter in your details get the page, goto source, and read the record.
Groningen civil registry, (Groningen, Netherlands), birth certificates (1816), archive number 1399, inventory number 6053, file number 917, Herman Levi de Vries birth certificate, 17 December 1816; digital images, AlleGroningers, (https://www.allegroningers.nl/zoeken-op-naam/deeds/bf10ebe2-0716-c08d-b30b-1b4b495b575d : 8 April 2020), image 489.
Layer 1 is the actual birth certificate. Layer 2 is the digital image. There isn't a "name" for the document, other than civil registry and they didn't film the cover or any frontpieces, just the first page of data. I'm not using a 3rd layer as WieWasWie was just a national index to get me to the regional archive. It's got great information, especially helping with translations, but it's not necessary to refinding the record or providing any insight into the veracity of the regional holding.