write function in another page and call that page to index.jsx

 car.js

function Car() {

  return <h2>Hi, I am a Car!</h2>;

}

export default Car;

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import React from 'react';

import ReactDOM from 'react-dom/client';

import Car from './Car.js';

const myelement = (

  <table>

    <tr>

      <th>Name</th>

    </tr>

    <tr>

      <td>John</td>

    </tr>

    <tr>

      <td>Elsa</td>

    </tr>

  </table>

);

const container = document.getElementById('sandy');

const root = ReactDOM.createRoot(container);

root.render(<Car />);

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call funciton in another function 

import React from 'react';

import ReactDOM from 'react-dom/client';

import Garage from './Garage.js';

const container = document.getElementById('sandy');

const root = ReactDOM.createRoot(container);

root.render(<Garage />);

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function Car() {

  return <h2>Hi, I am a Car!</h2>;

}

export default Car;

=

import Car from './Car.js';

function Garage() {

    return (

        <>

        <h1>Who lives in my Garage?</h1>

        <Car />

        </>

    );

}

export default Garage;

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