Sir i am pursuing diploma in mechanical engineering and after that i want to study b.tech, so what is the criteria for particular courses.
Diploma students can apply for direct into the second year of B.tech programme. There are many university offer the programme through their own entrance exam.
You can also apply for JEE Main Entrance Exam but you will be eligible to apply for IITs only so after qualify JEE Main Entrance exam, You need to appear JEE Advance Entrance Exam.
Good Luck!