Hi there. 

You are eligible to write NEET if you have scored 50% aggregate (for general candidates) in Class XII boards with Physics, Chemistry and Biology as the subjects. 

If you are currently pursuing your graduation it isn't necessary to complete it and then write NEET. You can do both at the same time. 

Like if you are in first year now and are willing to write the exam then you surely can. There are many students who do the same. 

But, keep in mind once you crack NEET, and get into a medical Institution you wouldn't be allowed to continue your B.Sc course. You can do only one course at a time. 

For checking the eligibility criteria of NEET kindly refer to the following link:

https://www.google.co.in/amp/s/medicine.careers360.com/articles/neet-eligibility-criteria/amp

Hey Sarkar,

Yes , once you graduate from B.Sc. Then you could apply for NEET. The 25 year old age limit which was previously their now has been removed. And Also it means that you have already passed +2 and yes you can apply. 

In order to be eligible for NEET 2019, it is mandatory for you to pass Class 12 or equivalent examination with Physics, Chemistry, Biology and English. if have completed education from outside the country must fulfill the NEET eligibility criteria 2019.

the entire NEET Elgibility criteria is given in the following website link,

https://www.google.co.in/amp/s/medicine.careers360.com/articles/neet-eligibility-criteria/amp

All the best!