I'm pursuing my bsc medical (2nd year) from panjab University and I'll be attending Cat 2018. how should i approach my cat from now on?

If you are looking forward to attend CAT 2018 then you need to start preparing right now. For quantitative ability You can start going through the basics from books like Arun Sharma which is pretty good and also start attempting questions of All difficulty level. You need to make sure that you make your basics very strong in quant because if your basics are not strong then you might fail get stuck in the tricky questions.

For verbal part you can start reading good novels by famous writers like Charles Dickens, read various  good newspapers like Hindu which will not only help you in improving your English but also keeps you updated with latest news. To improve on the reading comprehension section you can go through various passages and understand the thought process, tone of author and what message he/she actually wants to deliver. It's necessary to improve this interpretation skills because in RC section you won't find direct answers. For improving your vocabulary you should start memorizing 5 words daily with their meaning and correct pronounciation and use them in your daily conversations so you can memorize them properly.

Also along with this preparations you need to attempt lots of online mock test which will help you in overcoming your mistakes and come up with a strategy to attempt your paper which will definitely help you in improving your marks and percentile.For online mock test you can go through sites like oliveboard, Testfunda, hitbullseye etc. You can also take up test series of best coachings of India like T.I.M.E. and Career Launcher.

As you are a non engineer, you have a medical background so you have a plus point as you will be getting additional marks in aggregate score which is used to call students for interview round. This is done by college  in order to promote diversity in their college. Also in comparison to engineers you might get a call with lower percentile.

There is no as such good benefit of doing MBA from same university. I highly recommend you to prepare very well as you have enough time, score high percentile and get enrolled in best institute of our country like IIMs or some well reputated private  college.

All the best for your preparations and exams!!