I intend to get a second SIM to use for anything that needs security. Is there a practical way to remotely access an Android phone? Unattended, still works aft

I intend to get a second SIM to use for anything that needs security. Is there a practical way to remotely access an Android phone? Unattended, still works after reboots, not something like RealVNC (which needs UI interaction to begin session). I need security when traveling and so many important accounts (like my bank) want to use my phone as two factor. And my online bank portal locked me out for a month from overseas while traveling (some bug with their fraud prevention). I never ever want to deal with that again!!!