CAT

CAT is the biggest exam among the MBA entrances conducted in the month of November/December. In order to secure admission in a good college, rigorous preparation is required. CAT score is considered by almost every college except colleges who conduct their own entrances, such as Symbiosis (SNAP) and NMIMS (NMAT).
Post exam results, each college conducts its own GDPI process to evaluate the candidate. Apart from the exam score, performance in GDPI is equally important. A MBA candidate should have thorough knowledge about the current affairs.

As you are in 2nd year of B.Com and you are thinking of appearing in CAT than you must start the preparation. If you have good hands on basic maths (algebra, trigonometry, equations, coordinate geometry) than you can practice at home for logical and verbal. You can also join a coaching to sharpen your verbal skills. They do have a proper schedule and format of preparation. Along with coaching weekly tests will also assist you in your preparation. Even if you are not joining any coaching you must join a test series to evaluate your performance.

This is not a BBA+MBA graduate course. The IIMs are not allowed to offer degrees as of now. At the end of 5 years, you will get a Diploma. As to pursuing doctoral programs, there is no precedence for this as no student has opted for it till now, who was a participant in this course. But one thing is for sure, you won't have to give CAT to pursue those.

You can start your preparation topic wise. The time is less for preparation. So, you should start with logical reasoning and data interpretation. Also, go with English language. Then, go for GK and mathematical aptitude. Just create a time of the day and divide your day in four parts in which every part should be given equal weightage. This will help you in covering a large syllabus in less time.

Dear,
Find out if there is a TIME, IMS, Career Launcher, etc. coaching centres as these are the best coaching centres in India.

But they have already closed the applications for MBA.

TIME.
They provide not only good coaching and material for practice but also, they conduct various model exams every week and once the syllabus is over they conduct model exams every day for about 3 weeks.

Almost TIME Institute provide common coaching across India, and their faculty also good. Check near you to find out further, you should start your own preparation initially, at later stage take coaching. All the best.

To get a call from an old IIM, your focus should be on getting above 95% marks in CAT with sectional cut of around 80 percentile.
If you belong to reserved category, you can receive 80 percentile, then you can perform well at GDPI also.