issue #156: Introduction to Queue

[Subham5401]

Fixes #156

Short description of what this resolves:

new lesson: Introduction to Queue

What Changes proposed in this pull request:

• Added an introductory lesson on the Queue data structure.
• Explained the properties and operations of queues.
• Included a basic implementation of a Queue class using a linked list.
• Provided example usage of the Queue class.

Checklist

• Added description of change
• Added file name matches File name guidelines
• Added code examples, test must pass
• Added documentation so that the program is self-explanatory and educational.
• Relevant documentation/comments is changed or added
• PR title follows semantic commit guidelines
• Search previous suggestions before making a new one, as yours may be a duplicate.
• I acknowledge that all my contributions will be made under the project's license.

Notes: Added an introductory lesson on the Queue data structure, covering its properties, operations, and implementation using a linked list. This PR aims to provide a beginner-friendly explanation of queues and their usage in Java.