ICWA

3. I registered with Institute on or after 1st January 2008 but before registration for ICWAI course, I was undergoing Articleship training with Chartered Accountant or Firm of Chartered Accountants. Whether, articled training period with Chartered Accountant or Firm of Chartered Accountants will be recognized for the purpose of practical training period?

No, articleship training under Chartered Accountant(s) or Firm of Chartered Accountants is not allowed, whether taken before admission or during ICWAI course.

source : https://www.icwai.org/icwai/students-faq-trg.asp

To say simply,

It is not required to undergo articleship in icwai for the persons whom were not interested to go for practice.

=> articleship is required only if any body requires to keep practice as cost accountant.

the procedure for enrolling in ICWA -  https://www.icwai.org/icwai/index.asp