WASD to move the car (A/D for steering and W/S for accelerate/brake). Enter to read next in the dialogue. Left / Right arrow key to throw a package (those are the ones that must be delivered).

The goal is to throw the packages onto the delivery ramps which are located in the parking spots. The little thing danglig in front of your vehicle will guide you towards a random one of those.

You can also drift by holding left shift or space.

The original plan was to focus more on the delivering of packages and maybe have a short cute storyline, but this kind of ended up being an open world game.