VPN Setup Help

Hello,

This week I, for the first time, managed to setup remote connectivity, it is however through RDP

DynDNS =>
Port Forwarding 3389 =>
etc.

I would like to advance to the next step now by doing VPN connections.

Would someone please take the time to help me get everything in order regarding this plan?

I set the DDNS on the router not via the Update client on the server. This would then indicate to me that I must Port Forward from the Router, the VPN ports right?
What ports should i forward?
Do i need Real VNC on both Server and remote client using port forwarding?

Did i miss anything?