Is it not a bit more complicated than doing a bit of self study & sitting exams?
Learning air law (and all of the other topics) at an early stage is a great idea but there are lots of rules about the recorded ground training you have to have done, the length of time you have to do the exams, how many times you can take each one and how long the pass lasts before you have to take them again.
I would suggest looking up the CAA rules for the exams and making sure that you will be able to achieve your aims without wasting money. (If you can actually understand the current rules about the exams, you will have gone a long way towards getting a pass in air law!! )
