You are getting CSE in IIT Roopar. See there is nothing like chance reduced due to choice filling or preference order. When you have locked your choices and when seat allocation process begin then your first priority is considered the best for you and if your rank is sufficient for it you will be allocated the same. And if in case your rank is not sufficient then your second priority is considered and then your third and the process continues. So if you have put CSE Roopar at top and IIT Hyderabad after it then if you are allocated IIT Roopar first then you will not be allocated IIT Hyderabad in subsequent round because it is below the college allocated earlier. So fill your choices wisely. You xan take the help of JEE Advanced college predictor tool to predict your college and branch options based on your rank by clicking on the following link: https://engineering.careers360.com/jee-advanced-college-predictor?icn=QnA&ici=qna_answer

Hope it helps you.