Hi Nagendra,
If you want to start your MBA education in June 2019, you should have given CAT 2018. The deadline for the same is already over. If you have already applied it is good. Prepare for the same and you can get into IIMs or other B Schools basis your CAT score.

If not, some applications that may still be open are MAT,  CMAT, TISS etc. You can also look at admission tests by local colleges if you want to do MBA from any college.

However if you are looking at top B Schools. You can apply to the following next year (if you haven't done already) :
CAT
XAT
NMAT
TISSNET
IIFT ENTRANCE EXAM etc.