ONDC, or the Open Network for Digital Commerce, is a government-backed programme in India that aims to develop an open and compatible e-commerce platform.
Shopify is a popular e-commerce platform used by many businesses for their online stores. Nowadays Shopify's development is constantly growing. If you want to build custom apps for Shopify, you should learn how to use Shopify's APIs. You need to hire Shopify developers to get started with Shopify app development.