You'll soon be able to send and receive payments via the Google Assistant

Pay friends on Google Assistant
Once the new feature is released, you'll be able to use the phrase “Ok Google, send $10 to Jane for pizza,” and the rest will be done by Google Assistant. The only thing you'll need to take care is to make sure that your debit card is linked to your Google account.
Also, before the money transfer is approved, Google Assistant will ask for your fingerprint as a security measure. If you don't want to authenticate with your fingerprint, you can choose to use a security code to check out.
source: Google
Things that are NOT allowed: