Dear Kanika,

Yes a bio student can pursue IIT. There is no barrier in any stream. if you qualify the eligibility criteria of jee mains and jee advance then you can appear both the exams.

first you have to appear jee mains after that NTA board will release merit list for jee advance. You have to check you are there in the list. If you are then you have to prepare and appear JEE advance.

If you qualify jee advance with good marks then you can apply for counselling process.In counseling form you will fill college name and branch you want to opt for ,on the basis of those options and rank secured (reservation or general) counselling will be done and get an admission.There is no restriction in subjects and percentage of 12th.

Thanks