What should I do if I dont get a chance to get admission in IIM?

Firstly, be positive. Suppose, you don't get admission in any of the IIMs, then apply for other top B-schools such as FMS, MDI, IIFT, XLRI,TISS, IMT, SPJAIN, JBIMS,etc.

If you do not get admission in IIM, then you can opt for colleges like JBIMS, FMS, SP Jain, NITIE, NMIMS, and IIFT. These all are good brand names and have good placement assistance.