As a former ATPL theory instructor let me clarify the EASA ATPL exams.
1. The level is probably more like old "O" level standard - ask your parents.
2. You do not need to be academic but being able to do maths (sometimes mentally) is a must. Can you transpose & cross-multiply basic formula (distance speed time) and know some basic physics gas laws?
3. All schools study the same EASA syllabus but to mis-quote Eric Morecambe not necessarily in the same order (13 exams these days usually spread over 3 modules).
4. You need to think of them as an entrance exam to becoming a commercial pilot, it's a hoop you have to jump through.
5. In my & many other instructors views some of the syllabus is a farce most of which you will never use again. Why a pilot needs to know the constant of the cone of a Lamberts chart is my favourite useless bit of information.
6. It is the volume of high-class rubbish you have to learn in the time (8 months) that is the killer.
7. You shall have to put your social life on hold for the period as you will need 110% motivation & focus with no distractions.
8. Most students will spend another 3 hours+ study in the evening after the normal 6 hour school day.
9. Even with the best ground school tuition you are unlikely to pass the exams without the aid of question banks (QBs).
10. Why QBs - unfortunately the standard of the questions leaves a lot to be desired, the wording & meaning then the possible 2 correct answers but 1 is better than the other.
11. Certainly with the aid of QBs it is perfectly possible to average 85% across all subjects. Instructed several courses where the lowest average was in excess of 90% across.
I shouldn't concern yourself in what the ATPL syllabus is that's the schools problem. As suggested get a class 1 medical along with some PPL flying lessons & start your PPL theory.
If your parents are hell bent on sending you integrated ask them this :-
Most integrated ATOs require significant payments before you even start the course, the ground school would come first & even with accommodation & equipment would cost around £12k. Why do they want more of your money when they don't yet need it? If you still insist on this approach pay with a CREDIT card (not debit).
One last thought what does CAA stand for - Cash Again & Again.
If needed you can PM me.