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If you get good rank in  her advance than you will get IITs but if you don't get IITs than you don't get any good college in basis of jee advance rank. Most of the Colleges in India get admission through jee main. So jee  main rank will benefited you to get admission in other good colleges if you don't get any NITs.  You will get other good private engineering college.

But to get good college you need good rank in jee main

But now you should prepare hard so that you get admission in  IITs. 

Best of luck for your future buddy!