603 out of 720 in Neet 2020 means your expected all India rank would be around 6500 to 8500 and the expected percentile would be around 99.32 to 99.82. Now the score depends on various factors and the cutoffs do change every year. So it totally depends on what State you want to apply and if you want to apply under All India Quota or State Quota. If w ego through the cutoffs of various colleges, anything less than 550 for General category is less. Moreover, you belong to OBC, so chances are great. There are few states like Tamil Nadu, Karnataka, Uttar Pradesh etc have higher cutoffs while states like Himachal, Maharashtra, Assam, Tripura, Bihar have quite less cutoffs. And you cannot apply for State Quota of every single state which means you should also go for All India Quota. Unless knowing your state and category it is difficult to predict. However, in general, 603 in Neet is quite a good score for an OBC category candidate. You can expect a good government medical colleges in your State quota. I would suggest you to use our Neet college Predictor tool to know where you have good chances http://medicine.careers360.com/neet-college-predictor?icn=QnA&ici=qna_answer