Improve Documentation Clarity and Consistency in README

[Mefisto04]

• Updated phrasing for better readability and clarity in the Introduction, How To Install, and Video Understanding Task sections.
• Standardized terminology to maintain consistency throughout the document.
• Clarified instructions in the Quick Start and Environment Preparation steps for better comprehension.
• Enhanced formatting in the tables for a more organized presentation.
• No typographical errors were found; changes focused on enhancing readability.

These changes aim to make the documentation easier to understand and more user-friendly without altering the original meaning.

[Mefisto04]

hey @panregedit , please review this once and merge it