Google calls what you used “Google Prompt”. But there’s an alternative explained in 2.:
- true, not in App Lounge. If you’re really out to get it, Aurora Store will list it. But you do not need it, as…
- any Authenticator-type app will be able to import the timebased onetime password QR Code in Googles account settings.
A popular opensource Authenticator App to use is “Aegis”, you can find it in AppLounge. Make sure to backup the Aegis vault itself regularly - in doubt it can export to .html to just print it.
When logging in to web based Google things you can choose to enter the otp / authenticator type secret that Aegis (or any other otp App) will show at that time.