JSFiddle - React, Tailwind, and code Playground

HTML

<table class="tbl" Style="width: 30%">
    <thead> <tr>  <th>ID</th> <th>NOm</th></tr></thead>
    <tbody>
        <tr>  
            <td>1</td> 
            <td>TEST 1</td></tr> 
        <tr>
             <td>2</td>
            <td>TEST 2</td>
        </tr>
        <tr>
            <td>3</td>
            <td>TEST 3</td>
        </tr>
         <tr>
             <td>4</td>
            <td>TEST 4</td>
        </tr> 
    </tbody>
</table>



<table class="tbl" Style="width: 30%">
    <thead> <tr>  <th>ID</th> <th>NOm</th></tr></thead>
    <tbody>
        <tr>  
            <td>1</td> 
            <td>TEST 1</td></tr> 
        <tr>
             <td>2</td>
            <td>TEST 2</td>
        </tr>
        <tr>
            <td>3</td>
            <td>TEST 3</td>
        </tr>
         <tr>
             <td>4</td>
            <td>TEST 4</td>
        </tr> 
    </tbody>
</table>
<script type="text/javascript" src="https://mbt.dev.magiconline.fr/scripts/js/jquery.js"></script>

JavaScript

var T = [];

$('.tbl > thead > tr > th').each(function(){
	T.push($(this).text())
})

for (var i = 0; i < T.length; i++) {
	
	if (T[i] == "ID" ) {$('.tbl thead tr th').addClass('Myclass')};
}