Two-Factor Authentication: What is it and why do I need it to stay safe online?
https://blog.trendmicro.com/two-factor-authentication-what-is-it-and-why-do-i-need-it-to-stay-safe-online/
Google Authenticator
Apple https://apps.apple.com/us/app/google-authenticator/id388497605
Microsoft Authenticator
https://www.microsoft.com/en-us/account/authenticator
Authy
https://authy.com/
