Update README.md to include Deno setup and usage instructions

This commit updates the README.md to add setup and usage instructions for Deno alongside existing instructions for Node.js. It improves the document structure by separating the usage sections for Node.js and Deno, ensuring clarity and easy navigation for users working with different environments. - Adds a new section detailing the requirements and setup for Deno. - Revises the existing sections to accommodate the inclusion of Deno, maintaining a clear and organized layout. - Enhances the document's readability by appropriately spacing and titling each section.