Heyy Sarthak, 

Well Yes, there is no harm in taking a break from your graduation and preparing for the CAT. But make sure when you are taking a risk for CAT you need to give all your attention for CAT Preeparation. If you preparaing for CAT and doing Job at the same time you won't be able to concentrate on CAT as in job you have soo many responsibilities to be fulfilled. So, I would suggest you that if you are taking a break from your graduation for CAT preparation then pay all your attention towards CAT because at the end only CAT percentile will help you to get into the Best MBA colleges of India. 

All The Best for your CAT Preparation. Study with focus, avoid all those activites which distracts you and read newspapers daily for current affairs. 

All the best for a bright future !