HTML file not reading Javascript file in script – Blancer.com Tutorials and projects

I have the following issue. I have a HTML file called “GUI.html” and I’m trying to load a function from a Javascript file called “guiScript.js” but its only function is not recognized:

Html file:

<body>
    <h1>Selection</h1>
    <script src="guiScript.js"></script>
    <button onclick="obtenerEquipos()">Generar equipos automáticamente</button>
</body>

Javascript file:

import fs from 'fs'

function obtenerEquipos(){
fs.readFile('equipos.txt', 'utf-8', (err, data) => {
    if (err) throw err;
    
    // Converting Raw Buffer to text
    // data using tostring function.
    console.log(data);
})

}

Error log:

Uncaught ReferenceError: obtenerEquipos is not defined
at HTMLButtonElement.onclick (GUI.html:7:44)

Does it have anything to do with the import? I can’t think of anything else really. I’ve already read files this way before and it worked correctly.

Thanks!