Who was the first person to manufacture a car?

There's no single answer to who the "first" person to manufacture a car was, as it depends on how you define "car" and "manufacture." There wasn't a sudden invention; it was a gradual process of evolution.

However, Karl Benz is generally credited with creating the first practical automobile. His Benz Patent-Motorwagen, built in 1886, is widely considered the first true automobile to be commercially produced. While others built self-propelled vehicles earlier, Benz's was the first to be designed as a complete vehicle intended for sale and use as transportation.