Hello Aspirant

There are some eligibility criteria for ICAI and they are as follows

1. A candidate is eligible  for enrolment  to ATC after passing 10+2 and the common proficiency test
2. A candidate who has passed the exam is eligible to ATC course after complying to the relevant conditions

There is a registration procedure mentioned in the main link,you can refer is for further use:

https://www.icai.org/post.html?post_id=3919

Regards!