Complete the challenge in 90 seconds, and you will have to be very precise, so stop fulling around and do your job, i promise you it will be a trill.
Drive your vehicle to the spot where your cargo is resting, and try to connect it to the truck, but be careful, you can only do that if you are very precise, on the marked spot. You don't have to do anything, it will connect automatically.
The only way to open a new level is by completing the previous one. Try not to bump into walls or other trucks in the parking lot, cause you'll lose health and you can lose the level too.