it is not enough information bro at all
Frankly speaking, I would advise you to set up a server on Ubuntu. Windows Server 8 is no longer relevant and does not support most of the configuration. You can deduct more information on the Internet. But can I find out why you need this? It may be enough to buy a ready VPN, for example ipvanish review. Setting up your own VPN is a very complicated process.
Did you manage to create a VNP on your network?
I believe that all these efforts with setting up your own VPN, changing the configuration of your router, setting up ports, etc. not worth it. There are simple and at the same time multi-functional browser-based VPN extensions, such as https://chrome.google.com/webstore/detail/proxy-vpn-to-unblock-any/.... It also provides access to blocked sites and is very easy to operate.