hello ansh,
Different institutes have different criteria for ph.d admisssions.
the following criteris is for iit kanpur : https://www.iitk.ac.in/ee/admissions
and this is for iiser bhopal : https://www.iiserb.ac.in/doaa/phd-admission
both the links provided are of official sites, so you will get all the information without any ambiguity.
all the best!
Pursue M.Sc. in Data Science from Manipal Online.
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