JSFiddle - React, Tailwind, and code Playground

HTML

<div>
    <input type="text" /><br />
    <input type="text" /><br />
    <input type="text" /><br />
    <input type="submit" value="next" class="next" />
</div>
<div>
    <input type="text" /><br />
    <input type="text" /><br />
    <input type="text" /><br />
    <input type="submit" value="next" class="next"  />
</div>
<div>
    <input type="text" /><br />
    <input type="text" /><br />
    <input type="submit" value="next" class="next"  />
</div>

JavaScript

$('.next').click(function() {
    var missingRequired = $(this).closest('div')
                                 .find('input[value=""]');
    if (missingRequired.length) {
        alert('there were required fields that were not completed');
    }
});