Before users can do payments within the app, they have to create a customer.
For that, you have the endpoint:
post{{baseUrl}}/payments/customer-enrollment.
The onboardedcustomer will appear in Stripe's dashboard and you can easily see the info saved about them.
Customer Information in Stripe Dashboard
An advantage for when a user creates a customer with Stripe is that the bank that they will connect it with will be saved in the customer, and it can be used in the future without connecting a banking account again.