As I know if you use QB Billpay, you need to know your vendor's bank information to register. Another option, you can sign up for a free Melio account to integrate with QBO

https://affiliates.meliopayments.com/quickbooks

You can set Melio to ask the information.

You can also get a cashback to pay the first bill. Make sure to click the Get $100 cashback button to signup.

https://affiliates.meliopayments.com/cashback