The fan and the sail problem is with Newton’s third law. As soon as the air hits the sail, there is an equal and opposite reaction that negates the motion.
Putting a wind turbine on a moving vehicle would actually generate some power. You could charge a battery with it. But if you are using that battery to drive the car the charging won’t keep up with the discharging. If it could, that would be a violation of thermodynamics.
You will have to actually build this and demonstrate it under multiple conditions because no scientific based firm or organization will accept your proposal or provide funding. You’re better off investing your time and money in books about producing energy.