JSFiddle - React, Tailwind, and code Playground

HTML

<div class="about">
    <p>Hello</p>
    <p>Bye</p>
</div>

CSS

.fChar {
    color:red;
}

JavaScript

var x = $(".about p:eq(0)").text();
var text = '<span class="fChar">' + x.charAt(0) + '</span>';
$(".about p:eq(0)").html(text + x.slice(1, x.length));