IIT

Go through the link below for details:
https://www.shiksha.com/b-tech/ranking/top-civil-engineering-colleges-in-Maharashtra/53-2-114-0-0
For colleges in Gujarat, filter the state in the above link.

IIT Delhi CS branch is one of the most demanding branch now a day, so for getting admission, you have to score top marks in IIT exam. Then only you can get admission.

Yes, you are eligible as NIOS is also a recognized board.
Year of Appearance in class 12thDiploma Degree/Equivalent Exam for JEE 2018.Class 12th or Equivalent Exam Passed out candidates in 2016/2017. Class 12th /Equivalent Exam appearing candidates in 2018. Diploma Holders who have already passed or are in their final year of pursuing Degree.

All aspirants aiming to build their career in Science related fields must refer to the rankings mentioned at the link provided below in order to make a wise decision while selecting a college. After all, choosing a good college is the foundation stone to build a successful career later. Towards the end, we have also listed the top 50 B.Sc/ M.Sc. Colleges in India in 2016 as mentioned in India Today rankings. https://www.shiksha.com/science/articles/top-10-bsc-msc-colleges-in-india-blogId-13473.

No IITs and NITs provide BCA. But Many NITs provide MCA course!

Hi Divya!
You can pursue graduation in any discipline in order to appear for an IAS exam. There is no specification or restriction on the stream opted in your under graduation. The eligibility criteria only requires you to be a graduate from a recognised University.

The cutoff list varies every year but in Mains 50 marks are sufficient for SC candidates.

No, to join merchant navy, you have to be a part of IMU CET. This is conducted twice in a year. So, crack it with a smart rank, because only few seats are left.