Please share more details on your use for the APIs so we can better assist you.
Are you a merchant, acquirer, issuer, or processor?
What is the use case that you are considering using the Visa API for?
Who are your customers?
Which countries will you be using the API for?
Please also read through the API documentation on our website, as it provides detail information, how it works, requirements, etc.
VPP: Enables approved Visa clients to process card or token-based payment requests for Card-Not-Present processing scenarios. Please check out the How Does It Work section to see if this API fits your business use case.
Visa Direct: Enables the transfer of funds to eligible accounts.
For your second question: When you are ready to promote your project to the production environment, you will need to upload your own CSR as part of the Going Live workflow. Please check out the Going Live Guide for step-by-step details.
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