Last year some of my friends were also caught in this dilemma and wondered the same question. It is recommended to contact seniors from the colleges you want to compare through social media. Check out each college's gymkhana and college websites to see what events they are participating in. You'll get a sense of what kind of life you'll have in the coming 4 years. 

The following table shows a brief insight of both institutes:

There is no way to find everything in one college that you desire, and there will always be advantages and disadvantages. You should make the right decision for yourself if the available facilities and atmosphere will be productive to you or not. 

Now, for the IIT BBS electrical and mechanical departments, they have separate schools with full lab facilities on a permanent campus. The majority of the professors are from IIT Kharagpur, and they are all knowledgeable and helpful to the students, given that they are all highly qualified and experts in their fields.

ECE is in any way superior to Civil Engineering. NIT Trichy is also a really good institute, so don't just go for the IIT tag. Taking Civil in a new IIT (or even in an older IIT) will limit your options, in terms of location or something else. 

You might not get as many opportunities as you might get for ECE, given that the packages offered for ECE branches are comparatively always better. 

If you had the option of choosing a circuital branch in IIT BBS, then it would be highly recommended to you, but since you are considering Civil, it is a better choice.

To be eligible for admission, students must score at least 75% marks in 10+2 with Physics, Chemistry, Maths or Biology. The tuition fee to study CSE from IIT Bhubaneswar is INR 2,13,568 a year. The cutoff rank for CSE in IIT Bhubaneswar 1246-4068. The CSE department has seen 100% placement in 2019. The highest salary package offered was 39 lakhs per annum and the average salary package being 11 lakhs per annum. Some of the top recruiters that visited IIT Bhubaneswar include Amazon, HCL, IBM, Infosys, Samsung Electronics India, DRDO, Accenture, WIPRO, OYO, Adobe, etc. 

NITK Surathkal ranks 21st in the engineering category by NIRF 2019. The cutoff rank in NITK Surathkal for CSE ranges from 1000-1600. It has seen 100% placement in 2019 for B.Tech students among all streams. Some of the top recruiters include Bosch, ITC, Deloitte, Blue Star, Hero, HSBC Bank, Philips, Myntra, Coal India Ltd., Indian Navy, Make My Trip, Freudenberg, JP Morgan, Coca-Cola India, Tricon Energy, Oracle, Dell, Amazon, Adobe, etc. The highest salary package offered was 39 lakhs per annum and the average salary package of  14 lakhs per annum. 

CSE itself is a more popular subject than any other core engineering. Students get a lot of opportunities from many companies when they graduate from IIT or NITK Surathkal. So it depends completely on the decision of the student his or her JEE rank, location preference, choice of college, fees, etc. Both IIT Bhubaneswar and NITK Surathkal are equally good in placement and have a consistent record. So, you can choose to study CSE from IIT Bhubaneswar or NITK Surathkal.

IIIT Allahabad offers decent IT programs both at the undergraduate and postgraduate levels. The Information Technology department has more than 20 experienced faculty members.IIIT Allahabad also offers decent placements. In 2019, 95% of students were placed with the average CTC 15.5 LPA, while the highest CTC was 39 LPA.

The placement trends of ISM Dhanbad reveals Electrical engineering got around 75% of the placement in 2019 with an average package of 15.5 LPA. Students got placements in Google, Microsoft, JP Morgan, etc. to name a few.

In 2019, IIT Bhubaneswar had an 89% placement rate from the civil engineer department. IIT Bhubaneswar offered 53% placement in the core sector with an average CTC of 11.45 LPA and the highest package offered was around 39 LPA.

All the three options are good and have their own advantages, so choose according to your preference of course.

While choosing a course you have to take into account various factors like placements, relevant subject matter, fees, faculty, campus, etc. Below are a few pointers that may help you gain some clarity to make the decision. 

The four-year program at IIIT Gwalior consists of subject matter which is current and industry requirement oriented. Some of the subjects included in the course are Data Base Systems, Object Oriented Programming Language, Data Mining and Data Warehouse, etc. In the 7th and 8th semesters, the students can choose an elective from a list of subjects which include Artificial Intelligence and Machine Learning, IoT, Cryptography and Network Security, Quantum Computing, and many more.

IIIT Gwalior has introduced B. Tech-CSE in the year 2017. Therefore, students pursuing the course will have placements in the year 2021. However, companies like Swiggy, ONGC, RedBus, Aditya Birla Group, and many more have visited the campus to recruit M. Tech and MBA graduates.

The Mechanical Engineering course at IIT Bhubaneswar is tailor-made as per a student’s learning and career goal. The campus hosts a state of the art laboratory facility for the students to undergo practical learning of the theoretical concepts. Some of the subject matter included in the course are Engineering, Mechanics, Design, Machine, etc. The students can opt for an elective in their 7th and 8th semester from a list of subjects which includes Artificial Intelligence & Neuro-Fuzzy Theory, MEMS & Microsystems Technology, Experimental Fluid Mechanics, and many more.

In the academic year 2019, 83% of students of Mechanical Branch have been placed. PSUs like DRDO, ONGC, HPCL, IOCL, etc. visited campus. The highest number of companies visiting the campus were core industries. The average package offered was 11.44 lakh per annum.

Both options have their own pros and cons. Therefore, choose wisely according to your convenience.