JavaScript: Add hint to Iterate Through an Array with a For Loop (#19217)

* JavaScript: Add hint to Iterate Through an Array with a For Loop

Add hint to Iterate Through an Array with a For Loop (https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/iterate-through-an-array-with-a-for-loop and https://guide.freecodecamp.org/certifications/javascript-algorithms-and-data-structures/basic-javascript/iterate-through-an-array-with-a-for-loop)

* Update index.md

client/src/guide/english/certifications/javascript-algorithms-and-data-structures/basic-javascript/iterate-through-an-array-with-a-for-loop/index.md

@@ -1,10 +1,70 @@
+---	
+title: Iterate Through an Array with a For Loop	
 ---
-title: Iterate Through an Array with a For Loop
----
+
 ## Iterate Through an Array with a For Loop
 
-This is a stub. <a href='https://github.com/freecodecamp/guides/tree/master/src/pages/certifications/javascript-algorithms-and-data-structures/basic-javascript/iterate-through-an-array-with-a-for-loop/index.md' target='_blank' rel='nofollow'>Help our community expand it</a>.
-
-<a href='https://github.com/freecodecamp/guides/blob/master/README.md' target='_blank' rel='nofollow'>This quick style guide will help ensure your pull request gets accepted</a>.
-
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+
+Here’s the setup:
+
+```javascript
+// Example
+// Example
+var ourArr = [ 9, 10, 11, 12];
+var ourTotal = 0;
+
+for (var i = 0; i < ourArr.length; i++) {
+  ourTotal += ourArr[i];
+}
+
+// Setup
+var myArr = [ 2, 3, 4, 5, 6];
+
+// Only change code below this line
+```
+
+We need to declare and initialize a variable ```total``` to ```0```. Use a ```for``` loop to add the value of each element of the ```myArr``` array to ```total```.
+
+We start from declare a variable ```total```:
+
+```javascript
+
+// Only change code below this line
+var total = 0;
+```
+
+Next, we need to use a ```for``` loop to add the value of each element of the ```myArr``` array to ```total```:
+
+```javascript
+for (var i = 0; i < myArr.length; i++) {
+
+}
+```
+
+Now we need to add each value of ```myArr``` to variable ```total```:
+
+```javascript
+for (var i = 0; i < myArr.length; i++) {
+  total +=myArr[i];
+}
+```
+
+ Here’s a full solution:
+
+```javascript
+// Example
+var ourArr = [ 9, 10, 11, 12];
+var ourTotal = 0;
+
+for (var i = 0; i < ourArr.length; i++) {
+  ourTotal += ourArr[i];
+}
+// Setup
+var myArr = [ 2, 3, 4, 5, 6];
+// Only change code below this line
+var total = 0;
+for (var i = 0; i < myArr.length; i++) {
+  total +=myArr[i];
+}
+```