Dear aspirant,

Hope you are doing well. As per your query you have not mentioned the category of the exam you want to know. In maximum of entrance exams no registration in needed again in 2nd round as long as you have had registration in first round. If you are alloted a seat in first round then it will go according to the process and if not then you will automatically go to second round. Now these criterias are a bit different for some exams. Please mention the name of the particular exam so that we can help you out with the exact details. Thank you.