CAT

To score well in CAT, you must focus on your strong subjects. You in need to practice the full length tests to complete you strong topics in time with high efficiency. Regular practice with timely revisions will definitely help you to get good score in CAT.

Admissions would be conducted by DTE for the next academic year. Under that CAT would be considered for All India Seats. The cutoff for the same is usually around 99.99 percentile.
Link: https://mba2017.dtemaharashtra.gov.in/StaticPages/HomePage.aspx

Yes, you are eligible for CAT, though your class 10th & 12th score will pose a problem in every college as most of the colleges including IIMs are now making profile based calls.

Yes, definitely it's enough.
Provided in this 6 month you work hard, keep practising, determined so that you get good percentile and become eligible for good colleges.
Best of luck.

Admission in MBA in DIT University is based on counseling on Merit based on valid CAT/ MAT/ XAT/ CMAT/ DUET-17 score and performance in Group Discussion and Personal Interview (GD/PI). If you have valid score in above mentioned MBA entrance examinations, then only you are eligible to seek admission in MBA at DIT University.

If you want to get admission in good colleges then you must take entrance exams like CAT, CMAT, MAT, etc., and CLAT is not an MBA exam. It's an exam related to law.
Or you can get admission without the exam but through management quota seat or means donation. So talk to the related colleges where you want to take admission regarding this.
I would advise you to take exam like CAT, CMAT, MAT, etc., and get a good percentile and get admission on the basis of your marks.
Best of luck.

Yash, it won't be a good idea to waste one year. What if you are not able to score good in CAT 2017 and don't get a good college. Better would be you join MBA in LPU. LPU has one of the best business schools with ACBSP accreditation and good placements. LPU's business school is having highly qualified faculty from IIMs, IBSs, IITs, etc who work hard to make the students learn the subject.
LPU makes extra efforts by providing special inputs in the form of placement classes for best placements of its students.