Hello Jennifer,

Absolutely Yes! 

NCERT is the best book for AIIMS exam. Mostly questions in biology especially those related to diagrams come from NCERT. Also, most A and R questions of PCB come from NCERT. For physics and chemistry, you have to consider reference books.

I advise that after studying NCERT, try solving previous questions or NCERT based questions to see your level of understanding of the book. 

Wishing you the very best of luck!