Hello aspirant, hope you are doing good.

So, firstly congratulations for your outstanding rank in JEE Mains, it's not at all easy and I'm sure you did your best, so kudos to you for that. Now, with your rank, even if you cannot get a seat directly, you have definitely good chances of getting a seat through CSAB round, because your  rank is very near to the cutoff rank. Now, cutoffs of CSAB are not really easy to predict because they totally depend on the availability of vacant seats ,so if there are  enough vacant seats, you can surely get a chance.

Hope this helps you. Good Luck !!