How can I process Apple pay in react native

It's my first time to use apple pay. I'm using react-native-payments library and I could get paymentToken but I cant understand how I can perform a payment process.The payment provider companey hyperpay provided me entity Id and Access token but I don't know how to use them, which information I'll send, for any link I will send information and which response I'll get. This is the function does Payment process as documentation mentioned

paymentRequest.show() .then(paymentResponse => {   const { paymentToken } = paymentResponse.details;     return fetch('...', {     method: 'POST',     body: {      paymentToken     }  }).then(res => res.json()).then(successHandler).catch(errorHandler);});