Hey there!

Well JEE mains is conducted for the admission of students at various technical undergraduate program at NITs, IIITs and GFTIs in Engineering, Planning and Architecture across the country.

Admission to these institutes is totally based on JEE mains and 12th board Exam score, However JEE mains is twice every year and consider only the best score from both sessions.

Hence you are able to apply for admission on the basis of JEE mains session 1.

-----Also you want to know about the colleges in which you may get admission based on the JEE mains session 1 score, use JEE mains college predictor tool https://engineering.careers360.com/jee-main-rank-predictor

I hope this info is useful!