Apple won’t be keeping all of the services in macOS Server after the next few months. In the meantime, we have a big old guide to read. I have some overlapping articles I’ve been working on, but I’d say we’re in a similar headspace. The Apple macOS Server Services Migration Guide is available at https://developer.apple.com/support/macos-server/macOS-Server-Service-Migration-Guide.pdf and covers bind, vpnd, freeradius, manual netinstall with bootp and tftp, apache, wordpress, CalendarServer, and ftp. It’s pretty technical, but nothing too crazy in there!
Overall, an easy read and I’m glad to see some content coming out to help admins!