Hello,
As per the eligibility criteria for LLB In IIT-KGP, candidates need to have passed graduation or post-graduation in any discipline with 60% aggregate, in case or SC/ST/PWD there's relaxation of 5%. So, it doesn't matter you have done BCA, if you fulfill the required aggregate according to your category then you can definitely pursue LLB from this institute.
Admission is done through the entrance test in online mode, and the questions come from the following sections along with their respective weightage:
You can get the sample paper at http://www.iitkgp.ac.in/files/llb_sample.pdf
For more details regarding this, visit the official website at http://www.iitkgp.ac.in/law
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