JSFiddle - React, Tailwind, and code Playground
HTML
<table>
<thead>
<tr>
<th>A</th>
<th>B</th>
</tr>
</thead>
<tbody>
<tr>
<td>
<select name="nm_pot_part_shortage[]" class="mySelect">
<option value="AA">AA</option>
<option value="BB">BB</option>
</select>
</td>
<td>
<input type="text" name="nm_maker[]" class="myInput">
</td>
</tr>
<tr>
<td>
<select name="nm_pot_part_shortage[]" class="mySelect">
<option value="AA">AA</option>
<option value="BB">BB</option>
</select>
</td>
<td>
<input type="text" name="nm_maker[]" class="myInput">
</td>
</tr>
</tbody>
</table>
JavaScript
// comment either one to test it out
// using name
$('[name=nm_pot_part_shortage\\[\\]]').on('change', function () {
var selectVal = $( this ).val();
$( this ).closest( 'tr' ).find( '[name=nm_maker\\[\\]]').val(selectVal);
});
// using class
//$('#myInput').on('change', function () {
//var selectVal = $( this ).val();
// $( this ).closest( 'tr' ).find( '.mySelect').val(selectVal);
//});