docs: Enhance 'Getting started' section in CONTRIBUTING.md for new contributors

Task description: The current "Getting started" section in CONTRIBUTING.md is very brief. For new contributors, especially students, steps like "Fork the repository" or "Submit a PR" can be confusing without direct guidance or links.

Solution:

I propose enhancing this section by adding more detailed steps or linking to GitHub's official guides for Forking and Pull Requests. This will make the onboarding process much smoother for newcomers.

Who can join or take the task:

I would like to take this task myself! As a first-year CS student, I can help make the language more accessible for other beginners.

How to join or take the task:

Please assign this issue to me. /assign