Why don't you go to a reputable training organisation (and there are several near you) and take an initial flight? Then talk through the syllabus with them. Because - yes you do need mental arithmetic. You need to be able to do weight & balance calculations on the move, you need to know the maths of navigation and the science/maths of weather. And the physics of flight, and airframes, and, and, and.
Wish you lots of fun, some frights and some of those obstacles in life which make you wonder "Can I really do this ?"
Like - after about 7 hrs of training and you still can't hold a hover....and your fist is getting tighter on the cyclic...I've seen people weep. And then at about 10 hrs, they smile and wonder what all the fuss was about. They're holding it perfectly still with just finger and thumb.
All of which is nothing compared to your first auto.
