Karthik, NTA did mention that Chemistry is not a mandatory subject for appearing for JEE Mains which is the most common entrance examination. Instead, students can opt for any vocational subject. And your Inter 1st marks are not counted. Only your Intermediate 2nd year marks are counted. So if you have passed in your 12th and have studied any of the vocational subjects and scored good. you are fine to study Engineering. But if you do not have any Vocational subject in your curriculum, you still can appear for JEE Mains. Now JEE Mains doesn't have a minimum aggregate criteria for admission to Government and Private Engineering Colleges. You need to have a minimum 75% aggregate ony if you want to join IIITs, IITs, CFTIs and NITs. So you have to pull up your aggregate atleast upto 75% in your 2nd Inter.