To be able to appear for NEET, you should have studied Pysics, Chemistry and Biology as your subjects in your 12th. But yes, in 2018 the Rajasthan High Court has passed an order stating that not studying Biology should not be a hindrance when someone has qualified in the entrance exam. Now the catch here is, if you want to appear for NEET you fill an application form and the NTA guidelines even in 2019 in its information bulletin state that Candidates who do not fulfil the eligibility criteria even if they apply, their application shall be rejected. Now Rajasthan is a State level Court and NTA conducts NEET at a National level. So even if this rule applies, it might apply to Rajasthan and not the rest of India. And NTA doesn't mention that Non Biology Students can give NEET. Rather, it says that non Biology students can study Biology as an additional subject and appear for NEET. If you are in class 11 right now, you can  take up Biology as an additional subject in your 12th and appear for NEET. You also can study Biology from NIOS to appear for NEET. But Biology is a mandatory subject.