It’ll be VoIP behind the scenes but you can get these small boxes that basically give you a phone jack on one end and encode everything as VoIP. The phone connected to it sees a POTS and has no clue it’s VoIP. Kinda like how it’s done with most ISPs boxes that give you internet, tv, telephone.

I think you can still request a POTS hookup from the carrier but that can’t be cheap and it’s VoIP shortly after anyway, it only makes the copper pair to the VoIP box longer than if you do it yourself.