hi,

see iisc bangalore is most sought institute for its academic profile, laboratory and research collaborations. iisc sc offer 4 years bachelor of science course in physics, biology,  Chemistry, Earth & Environmental Science Materials, Mathematics. now coming to admission admission is based on kvpy score/ scb channels or jee main score. so the competition is quite high, depends on certain factors like number of participants, questions difficulty level, seat matrix, students category. however if you score more than 95 percentile in jee main exam you have fair chances.

hope you may understand.