This guide will help you configure VPN servers as a proxy in your Safari browser (Mac OS).
Open Safari Menu and click on Preferences
Then go to the Advanced tab and next to the Proxies you will see a button Change Setting, click on it.
Then check the "Web Proxy (HTTP)" option and enter the below details:
Secure web proxy server: The server that you wish to connect. You can check the list of servers here
Port: 8080 for HTTP/HTTPS and 1080 for SOCKS.
Check the option "Proxy server requires password" and enter your VPN login details
Repeat the same for "Secure Web Proxy (HTTPS)"
4. Click on OK to save the settings and now you can start browsing.