Unresolved function or method render() for React Hello-World app in IntelliJ

I used create-react-app to create a hello-world React application, then I used IntelliJ IDEA to open the application. But there is a warning for the index.js as following. I was wondering how to get rid of this warning.

This is a hello-world application created by create-react-app and I guess it needs to install some library in IntelliJ IDEA:

import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './App';
import registerServiceWorker from './registerServiceWorker';

ReactDOM.render(
    <App />,
    document.getElementById('root')
);
registerServiceWorker();