<script>
function AddRow(){
const tableElement = document.getElementById('table')
const newRow = '<tr><td>new Row</td></tr>'
tableElement.innerHTML+=newRow
//OR
// Add a single row element with `tableElemenet.appendChild('tr')`
}
</script>
<button onclick='AddRow()'>Add Row</button>
<table id='table'>
<tr><td>row1</td></tr>
</table>