JSFiddle - React, Tailwind, and code Playground

HTML

<form id="dummy">
    <input name="item1" value="field1" />
    <input name="item2" value="field2" />
    <input name="item3" value="field3" />
</form>

<form id="real">
    <input name="item1" value="" />
    <input name="item2" value="" />
    <input name="item3" value="" />
</form>

JavaScript

$('#dummy input').each(function(){
    if($('#real input[name='+$(this).prop('name')+']').length == 1)
        $('#real input[name='+$(this).prop('name')+']').val($('#dummy input[name='+$(this).prop('name')+']').val())
});