One situation where my car isn't moving and it's being acted upon a balanced is if the car was in the garage and its parked then gravity would be the only force acting upon the vehicle.
2nd Situation is if my car is driving on a straight road and is at a constant speed.
A situation where unbalanced forces are changing the speed/direction of the car would be if my car was driving and I have to turn so then my car uses friction to kinda slow down so turning the corner would be an unbalanced force because it's not at a constant speed.