React 16 not working in IE11, blank screen

I got these errors in IE11 and the React app was not rendering in IE11, it just shows a blank screen.

SCRIPT5009: 'fetch' is undefined
main.chunk.js (1020,3)

SCRIPT5009: 'Promise' is undefined
1.chunk.js (29037,9)


Fix,

Installed whatwg-fetch  and @babel/polyfill

npm install whatwg-fetch --save
npm install @babel/polyfill --save

After installation we need to include it in index.js

import 'whatwg-fetch';

import '@babel/polyfill';

This has to be done before importing React.