CAT

Yes, Final year students are eligible for CAT 2018 Exam. If you are graduating in 2019 and GD PI is held in Feb-Mar 2019, then you are eligible for admission in 2019-21 batch.

Yes, you can take admission because they take their own entrance exam.

Minimum 2-3 hours, put all your effort in preparing for exam, no distractions. Start from Quantitative ability, then work your way till Verbal reasoning, and do it for 6 months at least. Do it in the sense for cracking IAS exams, so it will be useful for other exams other than CAT itself. Follow newspapers study page, they update you with the latest questions and youtube tutorials for faster tricks in Math and reasoning. You'll be ready to crack any exam leave alone CAT.

NITs Rourkela accept CAT percentile above 50. The more important thing is your B.Tech percentage. It should be more than 65. And then, there is GD-PI. Total seats available is 60.

For IIM, CAT is must for admission. But, for rest of top B-School, you can give different entrance exams along with CAT like SNAP for Symbiosis University, XAT for XLRI-Jamshedpur, and lots of top B-School also accepts the score of entrance exams like MAT CMAT ATMA. So, choose the college first, and then prepare for entrance exams that accepted by that college.

No Sir, because the minimum criteria for pursuing MBA is 50% in graduation.

Go through the IIM call predictor below for details:
https://www.shiksha.com/mba/resources/iim-call-predictor.

Admission to FMS MBA programme will be based on extempore speech, personal interview & CAT. Applicants who have not taken CAT will not be considered for admission.

Overall, the cut off of IIM Ahmedabad is 80 percentile & above. Quantitative Aptitude (QA), Data Interpretation & Logical
Reasoning (DILR) and Verbal and Reading Comprehension (VRC) in 70 percentile for general category.

Overall, the cut-off of IIM, Ahmedabad is 80 percentile & Quantitative Aptitude (QA), Data Interpretation & Logical
Reasoning (DILR) and Verbal and Reading Comprehension (VRC) in 70 percentile.