As you want to get the details of process to become a CBI officer after completing B.Com so here is the information of the same for you:

Step 1:
First step is that you have to procure the “Application Form” along with required information from the employment newspaper generally published in the month of April

Step 2:
Candidates have to appear for the Preliminary Examination in the May or June the aspirants have to take the “Preliminary examinations” consisting of two papers.

Step 3:
If candidates has cleared Preliminary Examination then that candidate has to appear for Main Examination and final examination will consists of two part A and B

Step 4
If you have passed main examination then you have to appear fior the Personality Test