@publickovacs while this can help you understand how it all works. It won't directly tell you how.
But, you just need to go to settings > account > two-factor auth and scan the code with google authenticator or similar app. and input the code you see on auth app into the text field on the two factor screen on the computer. https://counter.social/apidocs/client/authorized/index.html
@MrGoat
Thank you!