JSFiddle - React, Tailwind, and code Playground

JavaScript

function titleCase(str) {
  str.toLowerCase();
  var strAr = str.split(" ");
  for(var i=0;i<strAr.length;i++)
  {
     strAr[i] = strAr[i].charAt(0).toUpperCase() + strAr[i].substring(1).toLowerCase();     
  }
  str = strAr.join(" ");
  return str;
}

alert(titleCase("I'm a little tea poT"));