As u suggested,I have been using NCERT for NEET preparation.But the problem now is I can't focus on my state HSC studies.

Preparing for both the exams require persistent effort and you should be able to manage your time. You can do your preparation along with Class XII Board Exams for that you have to managed through a customized preparation strategy and an approach for both exams. First, you have to analyze previous year questions papers, from their you will get to know importance questions and weightage of the topics as studying the vast syllabus of board exam along with NEET can be really challenging. You can draw matrix of chapters as per their weightage. The chapter matrix helps you to create checklist regarding time allotment, revision and highlighting the important facts related to the same. Focus on the Concepts- You should have clarity in concepts of Physics, Chemistry and Biology and they should thoroughly brush and revise the topics. The best way to do this is to take mock tests of the revised chapters. Plan your study schedule: planned your study schedule in such a way that you learnt and revised the chapter of the board exams and practiced the same for NEET.