Activate network lock on system start up

[Guest]

I'm using Eddie client on the newest MacOS. Eddie has an option to Activate Network Lock on Startup. However, I want Eddie to Activate Network Lock on System Startup. This means that my mac should have no connectivity till I turn on AirVPN.

 

I'm assuming Eddie is not able to achieve this because it will require admin privilege from the user . But is there a way to set such a firewall rule manually? I saw an old post https://airvpn.org/topic/1713-win-mac-bsd-block-traffic-when-vpn-disconnects/ that addresses this issue. But I want to double check whether it applies to MacOS 10.12 and whether the guide will conflict with the network lock feature now built into the Eddie. I'd also want to use local proxy like Tor for some traffic.