Get your mental arithmetic up to speed. Put the calculator in the bin.
The Scottish SQA school exams at national 5 level have a separate exam paper. Go to their website and enjoy.....you need to enjoy numbers to choose this as a career path.
Your Maths & physics will put you in sound position.
So long as you are not assessed as a "training risk" go for it.
As for the flying, hand to eye coordination is critical. Golfers with a handicap of ten or less will do well. Success at balls games is a valid indicator. Team player really important.
You peak at age 19. Post 30 ~ you will need to work harder to succeed.
Get an initial class one medical issued soonest.