Hey there, @darkstar057. Currently, QuickBooks Online (QBO) doesn't have a form for collecting customer credit card information. As a workaround, you can reach them and ask for the card information and manually enter it in the customer profile.
Here's how:
- Go to Sales and select the Customer tab.
- Pick the customer to whom you want to add credit card information. Then, Click the Edit icon.
- Scroll down and go to the Payments section.
- Select Credit Card from the Primary payment method section, and click the Enter credit card details.
- Once done, click on the Save icon.

Feel free to read this article for more details: Edit a customer's credit card information in QuickBooks Online.
However, if you have QuickBooks Payments, you can let your customers choose the credit card method and let them enter the details once they click View and Pay from the invoice email you send.

Moreover, you can visit this article to learn more about accepting online payments: Recieve and process payments in QuickBooks Online with QuickBooks Payments.
I'll also add this article if you want to learn how QuickBooks ensures the security of the cards used for payments: Learn about QuickBooks PCI Compliance.
Additionally, our QuickBooks Live Assisted is always available to help ensure that your customer transactions are accurate and on point.
Never hesitate to leave a comment below if you have additional questions about your customer's credit card information. We'll be willing to help as soon as possible. Take care always.