Help with configuration for a small AS (autonomous system), BGP, OSPF

I have a small AS to test/learn.
It currently consists of the following components:
- Own IPv6 /44 network
- Debian virtual server (host: vserver.site) in Frankfurt with BGP connection to KleyReX and LocIX, 100 MBit/s Hurricane Electric upstream
- Virtual Debian server (host: First-Root.com) in Düsseldorf, 1,000 MBit/s BGP upstream to the hoster
- GRE tunnel between the two servers above for communication between each other
- Virtual Debian Server (Host: Hetzner.de) in Nuremberg - Function: Nameserver
- virtual Debian server (host: ionos.de) - function: name server
- GRE tunnel between the two name servers and the virtual server in Frankfurt
- WireGuard tunnel between my home office and the virtual server in Frankfurt

Until recently, my IPv6 network was only advertised in Frankfurt. Now that it will be propagated in two locations shortly, I need help with the configuration. The aim is that my nameservers and my home office can always be reached, regardless of whether the data comes to my AS via Frankfurt or Düsseldorf. The whole thing should be able to be expanded with additional edge routers and server systems with manageable effort.

So I need help planning this small test network and configuring it.