It isn't as easy as on Linux, but you press Windows, type env, click edit Variables then select User vs. System, the you press add. That's not too complicated.
… And then you completely close all instances of the app that you need to see the changed environment variable, including any integrated terminal processes within that app. And then you relaunch all instances of that app and recover whatever workflow you were currently in the middle of.
That sets them globally, right? I need different variables and values in different contexts. e.g. in VSC I can set variables per-directory in settings.json files.
Windows has a GUI, how can it not be easy. /s
It isn't as easy as on Linux, but you press Windows, type env, click edit Variables then select User vs. System, the you press add. That's not too complicated.