There is no such direct admission process for iit bombay. It is a three step process. Eligible candidates are required to qualify JEE Main. Eligible candidates are required to qualify JEE Main.  Then after getting through the first stage, aspirants will have to appear for JEE Advanced. Admissions to BTech programmes at IIT Bombay will be based on the rank acquired in JEE Advanced. After the declaration of JEE Advanced results, eligible candidates will be required to appear for JoSAA(Joint Seat Allocation Authority) online counselling. 

no. for admission in any iits for btech you need to clear first jee main examination. if you qualify jee main you can opted for jee advance which is the only examination to get a seat in iits for b.tech programme.