I think NCERT itself is a sufficient resource for Chemistry for competitive exams. If you want to explore other books, then RC Mukerjee, O.P Tandon are good ones to start with.

After, Completing NCERT books you can refer below books to prepare for engineering exams

Physical Chemistry

O.P Tandon
P.Bahadur
R.C. Mukharjee

Organic Chemistry

O.P. Tandon
Paula Bruice Yurkanis
MORRISON & BOYD
Arihant
M. S. Chauhan

Inorganic Chemistry

O.P. Tandon
J.D Lee

All the Best!!