Several RUT140 and RUT145 units shall run as WG clients and connect to a single WG server. Resources within the LAN subnet of a RUT14x should be accessible via the VPN tunnel. For example, from a PC connected to the same server.
You wil have to forward ports from the Wireguard zone to the Lan zone under Network, Firewall, Port Forwards. I.e. if you want to reach a resource within the LAN on 192.168.1.10:100, enter a forward rule form external port 100 in zone Wireguard to internal port 100 on 192.168.1.10
Be carefull not to forward port 80 or 443 , otherwise you risk loosing access to the Teltonika Webgui.