To Show the alert, we will use a button as in html and handle the click event as in javaScript.

import "./App.css";

export default function App() {
 const showAlert=()=>{
   alert('You have clicked button');
  }

  return (
    <div className="App">
      <h1>Hello React</h1>
      <h2>Hello World!</h2>
      <button onClick={showAlert}> Alert </button>

    </div>
  );
}

as we can see that we have added onClick event and function name in { function } . We have added showAlert() fuction above the react return function, we have used javascript Arrow function

 const showAlert=()=>{
   alert('You have clicked button');
  }

This is how we have handled the clicked event and show alert on Screen. Follow me us on Linkedin: Swapnil Gupta Twitter: @Insanity_xi