Hi Visweswar.

It's a bit difficult to say which one is better among least ranked NITs and IIITs. At first, one can say that, go for NIT, and it is due to the name - NIT. It has an importance among the society. But, it is you who have to study there. So, before choosing any of these colleges, do conduct a research on them. Various factors like campus, lab facilities, infrastructure, faculties, placements etc. should be considered. And also, some courses in some institutions may be special. And, just go through NIRF ranking. you'll get an idea on the NIT/IIIT you're preferring. You have to styudy there for 4 years. you'll learn a lot from there. So, think well and choose.

Good Luck.