const App = () => {
  const pRef = React.useRef(null);

  React.useEffect(() => {
    console.log('DOM：', pRef.current);
  });

  return (
    <div>
      <p ref={ pRef }>Lorem ipsum dolor sit amet consectetur adipisicing elit. Obcaecati ad assumenda laborum id alias? Reiciendis fugiat, explicabo, natus aperiam debitis facilis quia consequatur voluptatum veniam nobis nulla ad perspiciatis in.  </p>
    </div>
  )
}

const root = ReactDOM.createRoot(document.querySelector('#root'));
root.render(<App />);