I guess want you wanted is using your Pi as both a web server to host your personal site and a VPN server for yourself to use. I think this can be done.
By taking a look at the link you mentioned, I think you are on the right track to install OpenVPN on our Pi.
However, there're one concern though. Many people use a VPN to hide their IP address as well. I guess your Pi might be sitting at your home and thus has your home's IP address. If you use it a s VPN server, your online activity will be associated with your own IP address.
To hide your home IP, you might have to use commercial VPN services as mentioned by other people above. Actually today there're many different VPN providers to choose from, each with different focuses, such as VPN for China
, VPN for torrenting, etc, you can choose one based on your need.
Anyway, here're some popular VPN providers (with reviews) that you might consider: ExpressVPN
, Total VPN