Company Secretary is a correspondence course.It is a programme which involves 3 stages:
1.Foundation Programme
2.Executive Programme
3.Professional Programme
After it one do 9 months training under practicing CS.

CS works mainly involve secretarial audit,corporate law,etc.

The student who would like to join the Course after 10+2 pass or equivalent has to undergo three stages to pursue the Company Secretaries Course i.e. Foundation Programme, Executive Programme and Professional Programme The Student who would like to join the Course after passing the Graduation has to undergo two stages of the Company Secretaryship i.e. Executive Programme and Professional Program

So depending upon your qualification you can apply for the respective program.

Rest info regarding course, syllabus, you can check below:

CS Course

All the best!