Architecture

You have good chances to get admission with this score. Keep trying hard, and in meantime do keep eye on other colleges too to have a safe hand.

Sir JJ takes admission on the basis of entrance exam.

Bachelor of Architecture (B.Arch) is a 5 years undergraduate programme, which can be pursued after 10+2 with minimum 50% marks with the compulsory subject of mathematics. Candidates can take admission in this course through the NATA/JEE Main 2 entrance test.

Go through the article below for details:
https://www.shiksha.com/architecture-planning/articles/top-architecture-colleges-in-india-mhrd-blogId-15727.

The final AIR will be declared after April 2019 considering the best score out of the two JEE Main attempts for all the applicants, hence based on current percentile we cannot predict whether you will qualify for NIT Rourkela or not. Wait for the final AIR declaration
Details:
https://www.shiksha.com/b-tech/articles/how-to-calculate-jee-main-rank-from-percentile-blogId-19953.

High chances that you can land in that college with that percentile.

Yes, you can easily get admission there with that percentile.

Yes, you need to upload the documents to the regional examination authority or go to the office of examination authority responsible for counseling and verify your documents.

Hi,
There are a lot of solved question banks for NATA and JEE Paper 2 exams, that would be helpful for you, more than this the sketching ability improvement would be a great addition for these exams.

Hi,
To prepare for NATA go through your 10-12th Physics, chemistry, Maths textbooks once again, also try a few drawing manuals. General aptitude and knowledge about buildings and materials would be helpful. There are a lot of solved question banks for NATA and JEE Paper 2 exams, that would be helpful for you, more than this the sketching ability improvement would be a great addition for these exams.