udpate invoking apis step00 readme

Author: shehza-d

step08_invoking_api/step00_invoking_rest_api_with_postman/readme.md

@@ -1,14 +1,18 @@
 # REST API Testing with Postman
 
-## [We will be doing Introduction to Postman course using Simple Books REST APIs](https://github.com/vdespa/introduction-to-postman-course)
+## [We will be using Simple Books REST APIs](https://github.com/vdespa/introduction-to-postman-course/blob/main/simple-books-api.md)
 
 [Download and install the Postman App](https://www.postman.com/downloads/)
 
+### [We will be doing Introduction to Postman course](https://github.com/vdespa/introduction-to-postman-course)
+
+### [Watch Postman Beginner's Course - API Testing Video](https://www.youtube.com/watch?v=VywxIQ2ZXw4)
+
 [Understanding the Basics of REST APIs](https://www.astera.com/type/blog/rest-api-definition/)
 
 [Sending your first request](https://learning.postman.com/docs/getting-started/sending-the-first-request/)
 
-[Watch Postman Beginner's Course - API Testing Video](https://www.youtube.com/watch?v=VywxIQ2ZXw4)
+
 
 Documentation: