The payment involves four steps :
a.) Integrating with server-side Initiate Transaction API()
This involves implementing the Call back API and above API
b.)Opening the ‘redirectionURL’ fetched from above API at the client-side. (https://developer.phonepe.com/v4/reference#open-phonepe-payments-page).
c.) Integrating with the Check Status API
d.) Integrating with the refund API