JSFiddle - React, Tailwind, and code Playground

HTML

<p> Enter text in the javascript function, and the capitalized text will be outputted below</p>
<p id="test"></p>

JavaScript

function ucfirst(field)
{
    return field.replace(/\w\S*/g, function(txt){return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();});
}

document.getElementById('test').innerHTML = (ucfirst('text here please'));