format number with commas and decimal as currency

Hi, I'm pretty new to js. I could use some help with this one. I'm loading a <input type="number"> element which will load a currency from the backend, but I need to create some kind of javascript function that will dynamically format the integer into a currency even when the user edits the number. For example, the page loads and the backend sends 1000.02 as the value for the element. It should display as 1,000.02 with commas and decimals in the right places. If the users decides to edit the number and change it to 1000000.02 than it should automatically add the comma as they type. I'm not sure how to call this function or how to use such a function. I was thinking of doing something like this

<?php
$data = new DataGetter; 
?>
<input type="number" onChange="currencyConverter(this)" value="<?= $data->getData(); ?>">

<script>
function currencyConverter(element){
    let input = element.value;
    let format = new Intl.NumberFormat("en-US", {
        style: 'currency',
        currency: 'USD'
    }).format(input);
    return format;
}
</script>

Any clue how to fix this?