Hello,

There are about 23 IITs in India located in different states.  If you meant Branches or subjects that are offered at IITs then there is a vast list of subjects. You can check official website of IITs to know about these subjects. Some of the branches may include:

• Aerospace Engineering
• Agricultural & Food Engineering
• Biological Sciences and Bioengineering
• Biotechnology
• Biotechnology & Biochemical Engineering
• Ceramic Engineering
• Chemical Engineering
• Civil EngineeringComputer Science & Engineering
• Electrical Engineering

Out of which CSE and EE is most popular among students and companies usually hire from these branches. Now talking about the ranking then IIT Madras kept its Rank No. 1 position in the 'Overall' category for the third consecutive year and the top spot in the 'Engineering' category for the sixth year in a row.

https://www.iitm.ac.in/

https://www.careers360.com/university/indian-institute-of-technology-madras

hope this helps!!