How to create API for connect or intergrate Webapp

How to create API for connect or intergrate Webapp to orders and manage member
for example
1, create QR code for table and custoner can scan fron webapp then user can select and submit order

  1. Manage member, member can topup or refill money cotar frm Webapp and link to terminal

  2. manage booking, user can see real-time table available and can booking