JSFiddle - React, Tailwind, and code Playground
HTML
<select id="estado" multiple>
<option>SP</option>
<option>RJ</option>
<option>AM</option>
<option>MG</option>
</select>
<div class="result"></div>
JavaScript
$("#estado").click(() => {
const estados = $("#estado").val().join(', ');
$(".result").html(estados);
});