Hello Aspirant,

Good to see your clarity and focus on future career at an early age.  Chartered accoutancy is one of the most respected and challenging profession. Usually ,it is difficult to clear all the levels in the first attempt but if you are hard working and determined ,it is possible. Accuracy is the most important skill needed here and practice is the only way to achieve  that.It takes the 5 years to complete the CA course and the 3 levels of this course are:

CPT (Common Proficiency Test)

IPCC (Integrated Professional Competence Course)

FC (Final Course)

Since CA is your interest ,it is better to stick to commerce with math, but students from other backgrounds are also eligible. After successfully completing your 11th and 12th in commerce you can either enroll for the foundation course(the first stage of CA course) directly or complete your graduation (preferably in B.Com) and then enroll for intermediate examination (the second stage of CA course.) i.e u can skip foundation.

By pursuing B.com many of the B.com subjects will be covered in the CA course and it will help you to crack both the exams without taking any extra effort for studies.

These article will be very useful to know more about CA,hence do check them out:

https://www.google.com/url?sa=t&source=web&rct=j&url=https://finance.careers360.com/articles/how-to-become-a-ca-in-india/amp&ved=2ahUKEwjhgIKbtofuAhWCzKQKHRm3BD8QFjABegQIAhAG&usg=AOvVaw1CZbfbMIYh8SLJcyRJszXq&ampcf=1

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.careers360.com/careers/chartered-accountant&ved=2ahUKEwjhgIKbtofuAhWCzKQKHRm3BD8QFjACegQIIBAB&usg=AOvVaw1YcthTfd2A_y2CZZWQYmfA

Hope it helps.

All the best