Recommended way to lock down internet to only specific applications within ubuntu-variant installation?

Trying to axe extra connections - ex: visualstudiocode wants to send some junk, and instead of going through the clunky settings there, I just wanna strip it of internet access except when I may want to. Any recommendations? I believe ages ago I saw someone show a command to container-ize just an executable for subset resources? Seems like if the symlinks or permissions were right it would be doable on linux? Thanks! Edit: Ideally I can just run a terminal command to disable/enable access to the internet when opening the application - or have two icons.. Edit 2: Reason for this, is I want to use the internet, but not have my editors or other non-essential applications taking up resources.