But unfortunately I can't tell you how to do that as it will completely depend on your network config...
If you are using consumer grade hardware to connect to the net then you'll probably need to configure the NAT and port forward to your VPN server. If your network is more enterprise level then you'll probably need to configure a firewall exception (although NAT may also apply...). Either consult the manual for your relevant hardware and/or your network/system manager (whatever is relevant).
You'll need to configure external access
But unfortunately I can't tell you how to do that as it will completely depend on your network config...
If you are using consumer grade hardware to connect to the net then you'll probably need to configure the NAT and port forward to your VPN server. If your network is more enterprise level then you'll probably need to configure a firewall exception (although NAT may also apply...). Either consult the manual for your relevant hardware and/or your network/system manager (whatever is relevant).