Hey,

Though the official cut-off marks of the topmost NITs in India have not released till now, it can be assumed as per the previous year's cut-off details that being a girl and belonging to OBC NCL caste you have to secure atleast 16-17k rank in JEE MAIN examination for get admission in such a prestigious institutions like NIT Agartala.

Hence I would like to recommend you to go through the following provided link minutely to be well-resourced about the last few years' cut-off details and other related information:

https://engineering.careers360.com/articles/jee-main-cutoff-for-nit-agartala

You can also check the Careers360 JEE  MAIN college predictor tool in this regard:

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

All the best !!! Hope this information and links will be quite helpful for you .