I figured it out, also in part because I got yet another guide:

https://github.com/bifravst/azure/pull/23/commits/4d86a0073b4cea45d59f5d747482f352560b9361
https://bifravst.gitbook.io/bifravst/bifravst-on-azure-wip/secure-azure-function-apps-with-microsoft-b2c