JSFiddle - React, Tailwind, and code Playground

JavaScript

function titleCase(str) {
  var result = [];
  str.toLowerCase().split(" ").forEach(function(smStr) {
    result.push(smStr.charAt(0).toUpperCase() + smStr.slice(1));
  });
  return result.join(" "); 
};

console.log(titleCase('dupa dupa dupa asdasdas dasd asd s'));