How to use React js in blade template

One of this way you pass data from laravel controller to react component.
A React Component interact with view id element document.getElementById('example') on your laravel viewpage. Your Laravel Controller like.

class HomeController extends Controller
{
   public function index(){
      $data = [
        'john', 'doe'
      ];
      return view('welcome')->with('data', json_encode($data));
   }
}

Make sure you passing data controller to view as json. Your Blade View

   ..
   <link rel="stylesheet" href="css/app.css">
</head>
<body>
    <div id="example" data='{{ $data }}'></div>

    <script src="js/app.js"></script>
</body>

Your Example Component in reources/assets/js/components/Example.js like

import React, { Component } from 'react';
import ReactDOM from 'react-dom';

export default class Example extends Component {
  constructor(props){
      super(props);
      console.log('data from component', JSON.parse(this.props.data));
  }
  render() {
      return (
          <div className="container">
            .....
          </div>
      );
  }
}  

if (document.getElementById('example')) {
   var data = document.getElementById('example').getAttribute('data');
   ReactDOM.render(<Example data={data} />, document.getElementById('example'));
}

Make sure, when you change of Example.js Component code then you must run npm run dev command on your command prompt.