var values = "JavaScriptTutorial";
var result = values.replace(/.{1,2}(?=(.{2})+)/g, '& ');
console.log("The actual result is=");
console.log(values);
console.log("After inserting space at nth position=")
console.log(result);

node fileName.js. 

PS C:\Users\Amit\javascript-code> node demo326.js
The actual result is=
JavaScriptTutorial
After inserting space at nth position=
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