See there are no direct recruitment process for the Research & Analysis Wing (RAW). The selection of the officers in RAW are selected from the IPS cadre. Thus if you wish to become a RAW officer, then you need to complete your 12th with any stream and then complete your graduation and have to prepare for the UPSC Civil Service Examination. The UPSC CSE is a 3 tier examination comprising of three steps namely, prelims, Mains & Interview. Depending on your score you will allocated the cadre. if you wish to go for the RAW then going for the IPS cadre will be prominent for you. The selection process is an internal matter of the RAW and no information regarding that isn't available online.

For more information regarding UPSC CSE consider the link below:

https://competition.careers360.com/exams/upsc-cse

I hope this helps. Wish you a great day!