Hello Kaviya ,

• To join CID, a candidate must have done graduation in any stream from a recognized university.
• A candidate who has already completed graduation can join this department as a sub-inspector.
• You join the police force, as a hawaldar or an assistant police depending on your qualification. After that you qualify the internal exams and apply to the CID department
• You could clear the UPSC exam, after Graduation any stream and join the CID team as an Assistant sub inspector
• There are many universities in India that offer degrees in criminology and criminal justice at the graduation level which may be helpful to join CID.

Note - Apart from qualifications and entrance exam, the candidate needs to be physically fit. At the same time must be a problem solver and must be ready to live under any circumstances and must have the ability to take risk.

Hope this helps.

All The Best !!!