I use Hushed app. It gives me a phone number that I can use for WhatsApp and to receive SMS confirmation codes from various archaic services that still validate you thorough the insecure SMS. https://hushed.com/
edit: but they have a dedicated UI to sell you number from a specific neighborhoods all over the US. I'm guessing their main market is online catfishers. (not saying the service cannot be a gvoice replacement, but catfishing is clearly their market)