Shakshi, NTA score refers to the percentile you obtained in the JEE Mains exam. It refers to your relative performance with respect to the other appearing candidate. That is, if you get 61 percentile, you performed better than 61% of the total candidates who appeared in JEE Mains January session of 2020.
You can calculate your approximate rank for JEE Mains using your percentile through the following formula:
(100-your total percentile) x 869010/100
So with 61 percentile, your rank would be around 338913.
Also, if the number of students increases to 12 lakh in the April session, the formula for rank calculation would change to:
(100-your total percentile) x 1200000/100
Hence your expected rank in this case would be around 468000.
While it is difficult to predict the exact qualifying cutoff, a percentile of 85 or above is decent enough to qualify for JEE Advanced for the unreserved students. In 2019, the NTA score cutoff for the Common Rank List was 89.7548849
According to your percentile, it will be difficult to clear the cutoffs for JEE Advanced. Also you won't be able to get a seat in the top NITs or IIITs with this rank. Although you can try for colleges through state level counselling.
I would suggest you to sit for the April session and give your best in that exam so that your chance of qualifying JEE Mains and getting a top college increases. Solve the previous years' papers, brush up your concepts and revise thoroughly.
You can also go through our college predictor to check which colleges you are eligible for through your JEE Mains score. The link for the college predictor is:
JEE Main College Predictor – Know your College Admission Chances Based ...
All the best.
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile