Add : in the end of sentense (#23916)

* Add : in the end of sentense

* Fixed typo and grammar

guide/english/redux/tutorial/index.md

@@ -53,7 +53,7 @@ project_root
   - /project_root/index.js 
     - Is the entry point for the app it will contain the entry point for which store, and it will render the the App.jsx file.
 
-Bellow is an example of the code that will be declared on the file
+Below is an example of the code that will be declared in the file:
 
 ```javascript
 import React from 'react';