JSFiddle - React, Tailwind, and code Playground

HTML

<script>
jQuery(function($){
applyField();
});
</script>

<select id="apply">
    <option value="email">Email</option>
    <option value="website">Website</option>
</select>
<input type="text" class="mygroup" id="email" placeholder="test@test.com" />
<input type="text" class="mygroup" id="website" placeholder="www.example.com" />
<textarea rows="4" cols="50" placeholder="text*"></textarea>

<input type="text" id="email" placeholder="test@test.com" />
<input type="text" id="web2site" placeholder="www.2example.com" />

CSS

.hidden {display:none;}

JavaScript

// Apply Fields
function applyField() {
    $(document).on('change', '#apply',function() {
        var selected = $(this).find(':selected').val(),
            elem = $("#"+selected);
        $(".mygroup").addClass('hidden');
        elem.removeClass('hidden');
    });
    $("#apply").trigger('change');
};