Yes there are few college which offers for b.tech in biotechnology. you can do B tech biotechnology even if you are a Biology student but yes not all the college offers B tech biotechnology to Biology students.

There are more college like NITs but they accept only jee mains .

And also you can go for vit. The name of vit entrance is VITEEE exam for btech biotechnology , the  least 60% in Physics, Chemistry, Mathematics/Biology and for sc or st the percentage is 50 %

For more information you can visit below link

About vit biotechnology , vellore

https://www.careers360.com/university/vellore-institute-of-technology-vellore/btech-biotechnology-course

Thank you. I hope this answer helps you.