Hello Sanjay,

The choice is yours. If you are willing to focus on getting good score in 12th you can pick up a normal coaching for 12th, or even self study using some amazing video lectures available on different platforms. But if you are focussed on the competition after 12th for various law, medical, engineering entrance tests for prime institutes you can take up a full year dedicated coaching for them, but mind you your 12th resultant score would be lower in this case than of the one stated formerly. 

All the best.