The famous medical courses are MBBS, BDS, Ayush and Veterinary courses. There are also other courses like Pharmacy, Agricultural Sciences, Physiotherapy, Occupation Therapy etc. All these courses demand subjects like Physics, Chemistry and Biology in your 11th and 12th. If you studied these subjects in your board exams, you can switch to Medical stream from Arts stream write relevant entrance examinations and study the medical course you are interested in. But if you didnt study these subjects in 11th and 12th, you cannot shift to Medical stream because mow rules have changed and you cannot pursue medical stream by studying  Biology as a separate subject. It should be your core subject.

Hello student No, you cannot change your stream from Arts to Science for pursuing your 12th standard. You have to pursue both 11th and 12th standard in the same stream whether it is Science or Arts stream. If you are interested to study game design in automation then, you need to study Arts stream not, Science stream. If you are interested to pursue Science stream then, you have to fresh admission in 11th standard Science stream as it is not possible to switch from one stream to another stream in 12th standard.

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Good luck