IIT Dhanbad (ISM) - Indian Institute of Technology (ISM) Answered Questions

Hello Dylan,
It's very nice to hear from you that you are interested in doing your graduation from the best institute. Being an IIT, this institution admits students based on your score in JEE Advanced. IIT's accept Diploma as equivalent to 12th and you should have scored at least 75% in Diploma to be eligible.
Best wishes to you.

I am neither a career advisor nor an educationist. I am an ECE graduate currently working as an IT/Software professional. Also, the answer caters specifically to the Indian engineering diaspora. So take my answer with a pinch of salt.
Short answer-
If you strictly have to choose between these two branches in the Indian academic system, go for IT if you want to be closer to a CSE program. The IT program though contains courses encompassing the management and commercial aspects of the industry, you'll still get the minimum or even more coursework required for a career as a software developer or computer scientist in the future.
ECE is what you get in a traditional EE program at the IITs curricula-wise, minus some advanced courses and those pertaining to heavy/power/systems/high-voltage engineering.
There is no question of better - both will teach you analytical skills - though IT will give you an edge in terms of campus placements in a tier-2/3 engineering college in India (ignore this aspect for a premier educational institution like the IITs). But again if you can write code or learn to write code while not being a CS/IT major, you won't end up broke when the dust settles.

You are basically asking about IIT. IIT doesn't provide lateral admission and not even regular admission through management quota. Your Diploma is however eligible for admission into mining engineering. I would suggest pursuing the course from another college.