JEE is conducted in Hindi and English language only. As long as you have the understanding of the subjects and a certain level of command on either of the two languages, I think you will be able to sail through. However, I suggest you start reading the NCERT and other entrance books in either of the two languages which you are comfortable with and practice a lot of papers till you get enough confidence. I think medical (NEET) may be held in your vernacular language but don't risk it and be prepared from your side.
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