JSFiddle - React, Tailwind, and code Playground

HTML

<div id="test"></div>

JavaScript

function removeRandom(str, amount)
{
    for(var i = 0; i < amount; i++)
    {
        var max = str.length - 1;
        var pos = Math.round(Math.random() * max);
        str = str.slice(0, pos) + str.slice(pos + 1);
    }
    return str;
}

document.getElementById("test").textContent = removeRandom("cat123", 3);