Off hand, I'd say you need a magnet and you need a car. If you want more specifics, then you must specify your magnet car with more detail.
For example, all electric cars, like the Tesla S, are magnetic cars in that all electric motors use some form of magnetism and electricity to create the motive forces that make the cars go.
So-called linear motors, where the stator is like a long segment of railing and the rotor is the vehicle itself, is yet another way of using the electro-magnetic flux to make something, like an elevator or train, go.
If you're talking about a small model car that can be made to move with a magnet, embed a small bar magnet in any non metal car you might have. Then bring a strong permanent magnet up close in front. The car will be pulled to the permanent magnet and move.