Hi Bharath7575,
Most years, the Average Score on the Official GMAT 'hovers' around 550 - so a 600 is 'above average' (and by extension, most Test Takers won't score that high). Based on your practice CAT Scores, you almost certainly have the skills needed to score at that level, but you have to be a bit more consistent about how you work through GMAT questions (meaning that you need to take the proper notes, avoid doing work "in your head", etc.). However you choose to proceed with your studies, it's worth knowing that you do NOT need to correctly answer ANY questions that you think are too hard or too weird on Test Day - so the best choice to make when facing those questions is to quickly 'guess' and move on. You can then use the time you 'save' on all of the other 'gettable' questions (re: the ones that you need to correctly answer to hit your Goal Score).
1) When is your Official Test Date?
2) Going forward, how many hours do you think you can consistently study each week?
3) When are you planning to apply to Business School?
4) What Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich