Civil Engineering

NSIT would top the list for the following reasons:
NSIT is among the top 10 engineering colleges in India, some consider it at par with the top IITs and better than newer IITs
The annual fees is less than Rs. 50,000/year
Most people will be willing to five times the fees to study at NSIT
The return on investment is huge, NSIT is probably #1 in India when it comes to placements. Facebook, Google, Amazon, McKinsey, Microsoft, Adobe and the likes are regular recruiters at NSIT. There's no cheaper college that's located in the center of the capital city of Delhi.

Hello Lavi,
It's totally dependent on your category because if you are from general category then it's a no. If you are from OBC-NCL then also still no. If you are from SC/ST, you can get a low ranked NIT with a civil branch. If you are from PWD, then yes in any NIT or IIIT of your choice with your favorite branch.

Manipal main campus is much better than the Dubai campus and it is very evident from the college rankings. Main campus definitely has better facilities, labs and even faculty.

Through ECET you can enter in B.Tech course if you missed to write ECET you can join in management quota.

Hello Sahana,Your rank of about 40K seems to be a bit on the lower side. However I am attaching a link that will predict college for you. https://www.shiksha.com/b-tech/resources/kcet-college-predictor.

You can try Thapar Institute of Engineering & Technology. First, preference is given to GATE qualifiers but after that vacant seats are filled by students who haven't appeared GATE as well. Plus, you have experience so that would give you an edge.