Hi @warrentab,
Thank you for your query.
There are many apps which you can use like Google Authenticator, miniOrange Authenticator, Lastpass Authenticator, microsoft authenticator, and others.
If you want to use OTP based authentication where one-time passcode is generated on your phone you can go with any application. The most popular app here is Google Authenticator.
But if you want to use QR-based Authentication(where you scan Qr to login) or Push based Authentication(where you can click on Accept to login) you should go with the miniOrange authenticator.
Once you install the app, You can go to the miniOrange Two Factor plugin Dashboard and select the choice of authentication method you want. Click on Configure and then scan the Qr code. Enter the OTP to verify and Save your authentication method(not in case of miniOrange Authentication Method). Then Test it on a different browser.
Let us know if you need more information.
Thank You.