Get your own React server
import React from 'react';
import ReactDOM from 'react-dom/client';

class Football extends React.Component {
  shoot = () => {
    alert(this);
    /*
    The 'this' keyword refers to the component object
    */
  }
  render() {
    return (
      <button onClick={this.shoot}>Take the shot!</button>
    );
  }
}

const container = document.getElementById('root');
const root = ReactDOM.createRoot(container);
root.render(<Football />);

              
localhost:3000