NextCloud with Wireguard: which ports to open to stay secure

Thank you Willi for your clear answer !

As said, I opened up the 51820 port on my server for Wireguard. I also installed the vpn client on my mobile. It works well.
But how can I access through the vpn my NextCloud (installed on the same Raspberry than Wireguard) ?
What address should I search for on my smartphone (or other device ) to connect NextCloud ?
Should I put some parameters to the installed Wireguard ?
Let me explain my installation:
Server:

  • Box from Orange (my ISP) to connect to the internet,
  • no fixed ip from internet
  • NAT open port for Wireguard: 51820
  • local network IP: 192.168.1.1
    Raspberry:
  • fixed local IP (192.168.1.25)
  • Wireguard installed, personaladdress.duckdns.org to solve the problem of the not fixed ip from my isp,
  • NextCloud installed

The personaladdress.duckdns.org ping is ok.
When I call with my smartphone (not connected in wifi) through the vpn :

I really wonder if I should add some parameters to the wireguard installation since Nextcloud is called with another port (9321) in this video https://www.youtube.com/watch?v=7Pe-Cv0tnLs (see captured screens). But I don’t know how to give this parameter to Wireguard… Andrea set up the install with Docker


SC Rasp1

In case you may help me solve this…

Thank you for your patience and help !
Dominique