Dear Akhin,

C. A. Course comprises of 4 Important Levels

1) Common Proficiency Test (CPT)
2) Integrated Professional Competence Course (IPCC)/IPCE
3) Three years Articleship/ Training under a Practicing C.A
4) C. A. Final

Register with the Institute of Chartered Accountants of India (ICAI) for Common Proficiency Test (CPT) after passing class 10th examination and you can appear for the CPT after your 12th class. 

Good Luck!!