JSFiddle - React, Tailwind, and code Playground

HTML

<table>
  <tr>
    <td>Harry</td>
  </tr>
  <tr>
    <td>Simon</td>
  </tr>
  <tr>
    <td>Maria</td>
  </tr>
  <tr>
    <td>Victory</td>
  </tr>
   <tr>
    <td>Victory</td>
  </tr>
</table>
<script>
    var tables = document.getElementsByTagName('table');
    var table = tables[tables.length -1];
    var rows = table.rows;
    for(var i = 0, td; i < rows.length; i++){
        td = document.createElement('td');
        td.appendChild(document.createTextNode(i + 1));
        rows[i].insertBefore(td, rows[i].firstChild);
    }
</script>

CSS

td {
    border: 1px solid #000;
    padding: 3px 40px;    
}