There are a few things that you would have to do in order to be a commercial pilot. The first is to obtain a pilot's license. This can be managed by signing up for a class at a local airport, many different companies offer them and they consist of learning the basics in classroom and in-flight instruction and eventually moving on to be able to fly solo and to build up enough hours to be granted a basic license.
To then move on to a commercial license requires further instruction and a relatively large number of hours of flying. Many pilots have met this requirement by flying in the military as they can accrue the necessary hours and some of the airframes and qualities of planes are similar.
Basically before becoming a pilot one needs science subject like phisics and so does one need to know about engineer and stuff that are related to mechanics