Steel or iron will usually do it.
tHERE ARE LOTS OF PARTS NEEDED
To create a car you need to know the material needed....chemistry, the way to build a car.... physic
In a car, a transmission system is needed because the engine does not make enough torque to make the car move.
what kind of stuff do you need to build a car
tissue box brass fastners and wheels motor wood
Many can build one if they choose to.
To build cars and make a profit.
In business it means that parts needed to build, say a car, arrive just in time, that is when needed, so there is no warehousing required.
the reason ehy they made the first car is becacuse the needed a to get around
Assuming you mean a toy car, build a "mouse trap" car and use your imagination.
This is kind of an open ended question, depending where you are on building your car. If you are starting at the frame, I would recommend getting a restoration guide.
You would probably have to build an extremely lightweight body of a car, with light wheels and pushbike pedals. It seems like a difficult feat, but if you have advanced engineering, the materials needed and determination, you could probably achieve it.