CA CPT Exam RELATED QUESTION

Hello everybody im mihir from chennai, i love accountancy ,commerce and business related subjects when im surfing on youtube a video came that some persons clearing CA exam under age 21 or above I currently at age 17 and im 11th grade students i have all the required study material can i apply CA CPT Course online and can i practice it.. and please tell me that how they managed to clear the ca exam in so young age please clear my doubts 

THANK YOU