how to return new array from array javascript with loo code example

Example 1: javascript loop through array

var myStringArray = ["Hello","World"];
var arrayLength = myStringArray.length;
for (var i = 0; i < arrayLength; i++) {
    console.log(myStringArray[i]);
    //Do something
}

Example 2: javascript loop through array

// looping through an array in javascript using our own myEach function

// Write an `Array.prototype.myEach(callback)` method that invokes a callback
// for every element in an array and returns undefined.
Array.prototype.myEach = function(callback) {
    for (let i = 0 ; i < this.length ; i ++) {
        callback(this[i]);
    }
}

let array = ['Item 1', 'Item 2', 'Item 3', 'Item 4'];

array.myEach(function (element) {
	console.log(element); // this will print each element in the array
    // Code to do something to each element in the array
});