The principle is about the same when creating a client configuration on Windows client for example. On Windows, you'll need to add a new interface using the WG client which will automatically contain a private and public key. The public key of Windows machine (the client) must be known on the server (RUTXR1) side and that public key must have its allowed IP address assigned.
Consecutively, the Windows client must know about a public key of the RUTXR1 on its interface [Peer] section as well as allowed IPs in the tunnel. You may choose to use a full tunnel by entering either 0.0.0.0/0 (or 0.0.0.0/1, 128.0.0.0/1) in the AllowedIPs line on the client side which, essentially, makes wireguard tunnel a proxy server.
As an example, I'm attaching my own WG configuration from my Windows client which is used to connect to my router (which acts like a server). Some settings like ports and IPs are different but the idea remains exactly the same. In this example I'm only trying to access the LAN resources (whole 10.10.35.0/24 subnet) behind my remote router.
[Interface]
PrivateKey = <Private key value of the Windows machine>
ListenPort = 55544
Address = 10.20.30.3/32
[Peer]
PublicKey = <Public key value of the router/server>
AllowedIPs = 10.20.30.0/24, 10.10.35.0/24
Endpoint = <External IP of the router/server>:55544
PersistentKeepalive = 30
If you still need some assistance with configuration, please generate a troubleshoot file from the router and send it over to me via private message. I'd like to take a closer look at your current WG configuration on the RUTXR1.
What's a troubleshoot file and how to generate it?
A Troubleshoot file contains the device's event logs, configuration files and other information useful for diagnostics. It can be downloaded from your device's WebUI, Troubleshoot page:
System → Administration → Troubleshoot
Best regards,
Tomas P.