Got a "You Joined Your Class" notification on my personal Windows 10 PC after signing into my school account.

GoGuardian allows a school or organization to basically spy on you. I was doing some schoolwork on my personal computer and I got a popup for it IN MY WINDOWS NOTIFICATION SETTINGS. I'm worried that they basically have access to my screen. It isn't installed as an extension on my personal Google account. Can they just see what's happening on my school account or my entire Google Chrome or my entire screen or what?

I've since switched to Firefox, but …

class pc personal privacy school signing windows windows 10