Sure! Here's an example of a simple 3D shooting game implemented in a single HTML file using JavaScript and enclosed in script tags:
To create an actual game with 3D shooting guards, you would need to add more code for player movement, shooting mechanics, enemy AI, collision detection, and rendering 3D objects. This example provides a basic structure to get started with game development using HTML and JavaScript.
Note that this code only sets up the canvas and starts the game loop. You would need to add more functionality and game mechanics based on your specific requirements.