Sure! Here's an example of a simple racing game with NPCs, boosters, a city to race in, and a leaderboard. Please note that this is a basic implementation, and you can customize and improve it further to match your requirements.
To play the game, open the HTML file in a web browser (preferably on a smartphone for better performance) and control the player's car using the left and right arrow keys. You need to avoid crashing into the NPC's car. Once the player crashes, a game over alert will pop up, prompting you to enter your name for the leaderboard. Your score will be displayed on the leaderboard, showing the highest scores achieved.
Note: This is a basic game implementation to give you an idea, and it can be enhanced with additional features, graphics, and optimizations as desired.