Fix#197

[Sri-dathu]

Summary of Changes:

• Added real-life examples for each OOP concept: Encapsulation, Polymorphism, Abstraction
• Modified OOPs.md to include these documentations and links
• Fixed minor formatting issues in the documentation.

Motivation:

This improves clarity for beginners and makes the OOP concepts easier to understand with practical examples.

Additional Notes:

documentation updates. and added code in OOP introduction

[Sri-dathu]

issue no #197 is solved and improved documentation