You can opt for Reset initialisation option which is available at the registration page. You can reset the previously filled quota choice and fill that details again and then move on to registration. You can use this only once and once you use the Reset option, you have to make a new registration with full payment of fees. And you can avail it in Round 2 as well. To make sure you are selecting the right Colleges and for a complete list of colleges that you may have a shot at, please use our College predictor: https://medicine.careers360.com/neet-college-predictor?icn=QnA&ici=qna_answer