Main 12 th main 70 % se hun scince se hun jnu main padhai karna chahta hun taki mujhe mere carriar main faida ho kis side se admition lun .
You can apply in JNU from.its official website.
Now if you want to do B.Sc then you can do it as there is no bsc in JNU. You have only a BA (Hons) option.
Follow the link for more information.
https://university.careers360.com/articles/jnu-eligibility-criteria
I hope this helps.