After the NOA2 and case is sent to NVC, NVC will assign a case number according to embassy
Not sure where u will interview as Netherlands no longer does IV (spouse ) interviews but if should start with FRN when you get notice of NVC received
Like FRN 2026xxxxxxxxx (for Frankfort) and using that number , you can lo into CEAC site to complete the I 864 and ds 260 by paying both fees allowing you to download all supporting documents
https://nl.usembassy.gov/immigrant-visas/
The U.S. Consulate General in Amsterdam will no longer offer routine immigrant visa services, as of May 2024. The U.S. Department of State has designated the U.S. Consulate General in Frankfurt as the processing location for immigrant, fiancée/fiancé(K), V92/V93, and Diversity Visa (DV) applications for citizens and residents of the Netherlands.