No, a 74.6% in Class 12th boards does not automatically qualify you for an M.Tech in Computer Science at IIT Bombay. While you can apply for JEE Main, you'll likely be ineligible for IIT admissions because of the 75% (or 65% for reserved categories) requirement for Class 12th marks. Your eligibility for IIT Bombay's M.Tech program will primarily depend on your GATE score and other requirements.