Initiate new session for a payment. This endpoint will help you get the paymentURL that you can use to redirect the customer to in order to complete the payment.
Any value you want to store with the invoice (you can get it later using the Payment Inquiry method). This can be a user identifier or a transaction Id in your system.
The payment URL that you’ll use to redirect the cusotmer to complete the
payment. It’s a link for a hosted page that will provide multiple payment
methods that can be choosed by the customer to pay the invoice.