Hi Gaurav,

                  I am here to help you with your query.IMUCET is the one way to join B.sc nautical colleges affiliated to Indian maritime university. It's ok if you are not qualified in that because there are colleges like which offer this course based on your JEE advanced exam like

                    * T.S.Chanakya marine engineering and research institution, Kolkata

                    * National Maritime Academy, Chennai 

       Some other colleges offering B.sc Nautical Science/B.sc Marine Science with their entrance exam are

                     * Tolani Maritime University      -       TMISAT

                    * West Bengal colleges              -       WBJEE

                    * Cochin University of Science and Technology     -    CUSAT CAT

                    * Vels University

                    * Mumbai University etc

       So If you are really passionate about Merchant Navy browse a lot then definitely you can find more colleges not based on IMU CET. I just provided very few of them.

All the best.

Feel free to ask your further queries.

Thank you.