I've completed 12th and want to do MCAT Between MBBS.So I wanna know what will be the earning after MCAT and Is it less than USMLE ??
You cannot take the MCAT during the MBBS, its an exam and not a course. Opting for the USMLE after the MBBS would be a better option.
The earnings will depend on the college you graduate from, and your specialisation. But the USMLE is a license to practise as a doctor, and MCAT is the exam to get educated as a doctor. You have to take both together to start earning.