Don't know why you're being downvoted. That is, in fact, the default. If you make any purchase, it prompts you for your google account password to confirm it's you and not say, your kid ot a thief mashing the screen.

You can set it to never ask to confirm your password, or to not ask if you already confirmed in the last 30 minutes (and there's one other time setting too, can't recall what it is). The "how often" is a separate option from the "how".

So, the "how": For conveniece and Google's never ending gluttony for more data, you can set it to use face recognition or fingerprint recognition instead of a password.

But they already have your password, of course. It's the password to your Google account, not anything new you'd be setting up.

That's all this is.

None of this does effectively anything if you don't have payment info stored, as you'd have to enter it first to make a purchase, then verify however ypu have it set up. The default way being password. And if you never purchase anything, just leave it with no payment info, and set to your password. No need to mess with the "how often" setting, it has no effect if you don't purchase anything.

TL;DR- Why are you booing? I'm He's right.