How can I boost internet speed while on the VPN?
maybe bandwidth limitation of your VPN provider
VPN slow down your speed not increase
If you are seeing slower speeds using VPN than without, on your normal internet, then it this is normal. The VPN throughput is generally lower since all the data has to be encrypted on your end and decrypted on the other end. Under average circumstances we are talking about 10-15% loss depending on the VPN server used and the type of VPN (IPSec, SSL, ...)
If you happen to have a really high speed internet (e.g. 50Mbit) the loss may actually be higher since VPN server generally have a limit in maximum VPN throughput they can handle duo to multiple factors (number of users, CPU performance and utilization etc.).
Another issue can be the bandwidth-delay product. When using VPN your traffic always travels between your client and the VPN server as well as the VPN server and the content in the internet. Depending on where the VPN server is this may be less than optimum. Imagine you are in the US and are using a VPN hosted in Europe. That's quite a large detour.
For increasing internet speed you should have high speed connection and avoid using free VPN they slow down your speed and show ads so you can't get fast speed.. You computer features should be new and highly updated as well
Can you give us some more details please? Which version of Windows are you using, and what VPN software (the built in Windows option, or a separate client such as Cisco)? Also, what kind of VPN connection is it? Is it used to access your workplace, your home network or to anonymise your access to the internet (this is highly relevant to the answer!).