Dear Mahalakshmi,

In order to prepare for GATE exam you can check the recommended books for electrical engineering below

Engineering Mathematics

Advanced Engineering Mathematics by E.Kreyszig

Electric Circuits

Transient Analysis Of Electric Power Circuits by Arieh L Shenkmann

Circuit Theory: Analysis & Synthesis by Abhijit Chakrabarti

Electromagnetic Fields

Elements of Electromagnetics by Mathew N. O. SADIKU

Engineering Electromagnetics by William H. Hayt

Signals and Systems

Signals and Systems by Oppenheim and Wilsky

Signals and Systems by Nagoor Kani

Electrical Machines

Electrical Machinery by P.S Bimbhra

Power Systems

Power Systems Engineering by Nagrath and Kothari

Power Systems by JB Guptha & CL Wadhwa

Control Systems

Control Systems Engineering by Nagrath and Gopal

Electrical and Electronic Measurements

Electrical and Electronic Measurement and Instrumentation by AK Sawhney

Analog and Digital Electronics

Electronic Devices and Circuit Theory by Boylestad

Digital Design by M.Morris Mano

Integrated Electronics : Analog And Digital Circuits And Systems by Christos C. Halkias, Chetan D. Parikh Jacob Millman

Power Electronics

Power Electronics by MH Rashid

Power Electronics by P.S.Bimbhra

Good Luck!!