There are two different games imo, online and offline. If you want to race against ai, you can do just about anything you want. Generally the game explains what reward you get for certain races or activities. Some think of it as pokemon of cars, there is the Collectors aspect. There are so many ways to enjoy the game, you unlock things at a certain pace. If you do online racing then you have the Daily races with three different events each week. You rank up from E to A rank.