There are many course for BTech in India. Some of them are the classical fields where as some of them are interdisciplinary and specialized fields.

some of the popular BTech courses are:

• MECHANICAL ENGINEERING
• ELECTRICAL ENGINEERING
• CIVIL ENGINEERING
• ENGINEERING PHYSICS
• AEROSPACE ENGINEERING
• COMPUTER SCIENCE & ENGINEERING
• ELECTRONICS AND COMMUNICATION ENGINEERING
• AERONAUTICAL ENGINEERING
• Chemical Engineering
• Information Technology

Now apart from this there are some applied fields and Interdisciplinary fields of BTech like:

• Genetical Engineering
• Biomedical Engineering
• CSE specialization in Data Science/ Artificial Intelligence/Machine Learning
• Mechatronics
• Robotics

To know more about this you may visit the link below:

https://www.careers360.com/courses/b-tech-bachelor-of-technology

I hope my answer helps. All the very best for your future endeavors!