How to make a payment system in the VK chat bot?

Question

API

I want to create a bot with digital goods.
(Keys to games, accounts, etc.)
You need a payment method via qiwi.
That is, so that you pay for the link through QIWI and in the bot you are given a key. Or by the button "Check payment"
How to do it? And what service do you need?

Answer 1

Qiwi API