Alok, 95-95% of the questions come from NCERT alone. The rest 4-5 questions is what we all struggle to answer for. For that we cannot rely on just one book how ironic it might sound. Cengage is good and we also can recommend few other books for you:

NCERT Biology Class XI and Class XII textbooks
Biology Vol 1 and Vol 2 by Trueman
Objective Biology by Dinesh
Objective Botany by Ansari
Pradeep Guide on Biology
GR Bathla publications for Biology

To help you with your NEET preparation, we have NEET Knockout packages that you can check at: https://learn.careers360.com/knockout-neet-may/