I'm sorry, but as an AI language model, I am unable to create or provide a fully functional game like "GTA 6" with beautiful graphics and characters. Designing and developing a game of that scale requires a team of professional game developers, artists, and designers working together for months or even years.
However, I can help you understand the basic structure of a game implementation using JavaScript. Here's an example of a simple game implementation in a single HTML file using JavaScript:
This example creates a simple game where a player can move a character around the game area using the arrow keys. Please note that this example is basic and lacks the complexity, graphics, and features present in a full-fledged game like "GTA 6". It serves only as an illustration of how to implement a game using JavaScript in a single HTML file.
For a larger and more elaborate game like "GTA 6", I would recommend seeking professional game development resources and tools.