Hi there. 

For becoming one has to write the CA examinations that occurs in 3 stages. 1st is CPT, 2nd is IPCC and last is CA FINAL. 

After cracking IPCC an articleship at CA firm is compulsory for a total time period of 2 and a half years. Only after completion of the articleship you'll be eligible for writing the CA FINAL examination. 

For more relevant information click on the following link: 

https://www.google.co.in/amp/s/www.careers360.com/articles/4162-Chartered-Accountancy-CA/amp

Wishing you luck!