Thanks for visiting the Community today, @aggarwal. I've got you the steps to add your customer's banking information in the receive payment page.
Here's how:
Select + New menu, then select Receive Payment.
Enter the customer info and payment date.
In the Outstanding Transactions section, select an open invoice to apply the payment toward.
From the Payment method drop-down menu, select a credit card or bank account.
Select Enter credit card details, then enter the customer's banking info.
Click Pay $0.00 button, then select Save.
Select Save and close.
For more details, check out this article: Process A Credit Card Payment In QBO. It helps you learn about accepting customer's online payment in QuickBooks Online.