threeseries on Nostr: What's the best setup for cellular / voice service that has good privacy / control ...

What's the best setup for cellular / voice service that has good privacy / control without too much inconvenience?

To start, I finally got around to setting up VOIP service on my device now that I'm getting crazy spam on my main cell line. I essentially want to deprecate this number and have a new one only for the occasional but mandatory 2FA SMS verification. Any ideas on how to approach?