A wheelwright is someone who builds or repairs wheels. In the olden days there were lots of carts. The wheels were made of wood. It was a difficult job to make them, so the cartwright made the cart and the wheelwright did the specialized job of making the wheels. In ancient times some wheels were made of bone in order to look beautiful.
The word wheelwright is not often used for people who make wheels today. Wheels are made in factories and lots of people on the production line each have their bit to do.