How to pass all throttled data traffic to an unthrottled port and browse internet at full speed

There are multiple TCP/UDP based VPN apps which can provide free internet. I'm no expert in this field but according to what I understand is that these apps can work if you are able to browse at least one website without any internet plan. They pass all the normal internet traffic through that one website so that your operator thinks you are still browsing that one free website. Can someone throw some light on how this process exactly works and can I use it to make my internet work faster because when I exhaust my data limit still some websites work at full speed.