Hey Helsinki ,
For your use case please take a look at this link for APIs specific to your use case - https://developer.visa.com/apibrowser
For online payments, I'm recommending you to take a look at the API links provided below.
Visa’s Payment Methods APIs aim to help process payments securely, safely, and quickly. Payment Methods APIs - https://developer.visa.com/site/payment-methods
Visa Checkout provides a single sign-in service to pay for online shopping purchases. After a simple setup, Visa Checkout users can skip inputting their payment and shipping information for their orders. Visa Checkout works across multiple devices so online shopping stays easy. Visa Checkout - https://developer.visa.com/capabilities/visa_checkout/docs
CyberSource Payments processes credit, debit and gift cards across the globe and across multiple channels with scalability and security. CyberSource supports an extensive list of payment cards and offers a wide choice of gateways and acquiring banks, all through one connection. CyberSource Payments - https://developer.visa.com/capabilities/cybersource/docs
Visa Direct offers real-time payment capabilities over Visa’s global, interoperable network. Businesses and consumers can make payments to eligible card accounts, using solutions developed with participating financial institutions or payment service providers. Visa Direct - https://developer.visa.com/capabilities/visa_direct/docs
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