Guide on using MFA

I’d like to enable MFA on HA as I have recently enabled access to my server across the internet using the DuckDNS addon. However I can’t work out how to do this in a way that I can still have access , from my local network , should I lose my phone. I have had situations in the past when I’ve also had to ‘fix’ my phone by resetting it to factory settings. Is there a guide on how to setup MFA that anticipates things going wrong ?