You basically lock your choices and you get selected based on your AIR .

There are 3 rounds in the process of counselling in which you also have to report to a reporting institute to verify your documents . This is usually after the first round .

After the first round if you haven’t gotten the institute you wanted you can opt for an upgradation which means the second round , so you fill your choices again and you get another institute as per your preference sequence , the same happens in the third round .

Also , in the next rounds if you don’t get the institute you wanted , you still have the one allotted to you in the previous round .

There are no further rounds , just an online process , that’s it .

All I’ll suggest you is put your preferences wisely , you never know , maybe you’ll get the institute you want in the last round!