Hello,

Just like UPSC , Uttar Pradesh PSC exam is conducted in three stages: Prelims, Mains, and Interview. You should start your preparation with with NCERTs for basic foundations and then move to the standard books as this will make your foundation stronger.

For Prelims, refer the following books:

History ;

NCERT Class XI and XII
India's Struggle for Independence by Bipin Chandra
For Indian Culture, refer art and culture by Nitin Singhania

Geography ;

NCERT Class VI to XII
GC Leong's Physical Geography
World Atlas

Economics ;

NCERT Class XI
Indian Economy by Ramesh Singh

International Relations & Polity ;

NCERT XII Political Science with current affairs
Indian Polity by Laxmikanth

CSAT ;

Verbal and Non-Verbal Reasoning by RS Agarwal
M Tyra's Quicker Maths

Coming to Mains Exam, you can refer the following books for four General Studies Paper;

GS I - For History , Class XI NCERT book with India's struggle for Independence by Bipin Chandra,India after Independence by Bipan Chandra,History of Medieval India by Satish Chandra

For Geography refer World Geography and Geography of India by Majid Hussain, GC Leong's Physical and Human Geography with NCERT Class XI book.

For GS II - Polity and International Relations , refer Indian Polity by Lamikanth,India's Foreign Policy by Rajiv Sikri

For GS III - For Economics refer Indian Economy by Ramesh Singh, read ARC report along with Economic Survey and Fiscal Budget.

For GS IV - For Ethics refer a book named Lexicon by Niraj Kumar, also you can go through study material of IGNOU.

Remember to keep resources minimal always, read one book many a times instead of many a book one time. In addition to this, do read The Hindu on a daily basis.