The game starts with a short tutorial - a "sandbox": you can examine three cars, there are a lot of devices and tools in the workshop and you can access test track which must be completed with one of the cars if you want to start the proper game. When you look at each device you get a short note which informs you about its properties (more detailed information about usage and property of devices can be found in Workshop's equipment chapter). When you are on the track you can see, in the upper left corner, three stages that must be completed. Only the last stage - braking - can cause you problems. You don't have to brake behind the green zone, you only have stop when you are on it, even if you are driving slowly.
When you complete the test track you can proceed with the main gameplay. Your workshop is much smaller than the one before. First, you must download an order. Open the quick menu (RMB) and press the phone icon. This opens the menu with available orders. They are divided into story and optional orders that will appear and disappear. You should download optional orders frequently when you don't have to use new parts or those that are in good condition - it is possible that you have those parts in your warehouse because they are left from previous repairs.