Interact with an overturned car to flip itAlthough it may look a bit complicated, this challenge is actually quite simple. You only need to find a car, which is running, and reverse it yourself. There are several ways to do this, but the easiest and the one that everyone can do quickly is to build a ramp and drive the car up it. However, you only have to mount the wheels on one side (right for example) for an imbalance to occur and the car to overturn.
Once it's on its side or on its back, all you have to do is approach the vehicle and interact with it to make the car turn around. You have thus validated this little quest and won the promised XP. You can then move on and tackle a new challenge.