Most students join IITs with the mindset of changing their branch to a more preferred one after the first year. But in reality, once you come here you will realize that branch hardly matters here. This is because most students, especially those with no specific area of interest, which seems to be your case too, tend to go for non-core jobs for which the branch does not matter. What matters is your CPI and your overall profile and achievements.

Those adamant about changing their branch can avail of the facility easily. The branch change depends on 2 factors, your CGPA and the availability of seats in the branch you want to get changed into.

• For Civil, Material Science, Aerospace, and Physics, you need a CGPA of around 6.5–7.5
• For Economics, Mathematics Scientific Computing, Chemical, and Mechanical you need a CGPA of around 7.5–8.5
• For Mechanical or Electrical, you need an 8.6+ CGPA
• For CS, you will need nothing less than a 10 CGPA in both the semesters 

Honestly, it’s almost impossible to get a branch change into top branches like Mech, Electrical, or CSE. The chances are rare but worth trying. Most companies consider students from all the departments for placements. So, IIT Kanpur is a good option whether you want a branch change or not.