Hello there,
There are plugin for chrome https://chrome.google.com/webstore/detail/avast-secureline-vpn/phmegojolgpbbcnhccbfneddlooepbpd?utm_campaign=Use%20extension%20install&utm_source=Settings
But there no option to up vpn over vpn. like it’s work at cyberghost for example or nordvpn. it’s allow only change in vpn program.