Hello aspirant, hope you are doing good.

Firstly, congratulations for your great preparatory rank, you got an additional chance to get into your dream IIT, make sure you make good use of it. Now, preparatory ranks are for preparatory courses, you will be trained under an IIT according to your rank, and after a year, you have to give an exam, based on that if you pass or fail, you will get a confirm seat in an IIT.

Now, you have a great rank, so you are most likely to get the top IITs that provide preparatory courses, you will know which one you will get in the counselling.

Some of the IITs that provide preparatory courses are:

1.IIT Roorkee

2.IIT Delhi

3.IIT Mandi

4.IIT Guwahati

5.IIT Kharagpur

6.IIT Bhubaneshwar

7.IIT Patna

8.IIT Madras

9.IIT Bombay

10.IIT Hyderabad

If you want to know about all the possible colleges you can get into with your JEE Advance rank, you can get it here:

https://engineering.careers360.com/jee-advanced-college-predictor?icn=QnA&ici=qna_answer

Hope this helps you. Good Luck!!