Aerodynamics is not an easy subject, lots of maths, fluids mechanics, thermodynamics, and so on are involved.
But this book is the easiest way to initiate yourself into this topic.
Maths are contained in a reasonable complexity with a step by step, plenty of explanations, demonstrations.
There are also a lot of examples, figures, tables, and pleasant historical notes about the aerodynamics founders and milestones.
So this book is the ideal first book on aerodynamics, from which you will understand the subject, and maybe later, you will jump into a more specialised text.