JSFiddle - React, Tailwind, and code Playground

HTML

<input type="checkbox" value="cat">Cat<br>
<input type="checkbox" value="dog">Dog<br>
<input type="checkbox" value="turtle">Turtle<br>
    <div id="demo"></div>
<input id="button" type="submit" value="Submit">

JavaScript

$("#button").click(function() {

var x = $("input[type=checkbox]:checked").map(function() {
     return this.value;
}).get();
$("#demo").append(x.join(", "));
    
});