Hello Rohan ,

Here is the list of few important general knowledge topics:

1. Coucil of Ministers of India in NDA

2. International Organisation Heads.

3. Country's capitals and currencies.

4. All presidents and prime ministers of India.

5. Important days and dates.

6. Ancient Indian Scientists.

7. Bharat Ratan Receipients

8. Indian nobel prize winners.

9. Airports in India

10. Important dances of India.

Some of the books you can refer are :-

Lucent's general knowledge book, Manorama yearbook, objective general knowledge, general study paper 1.

Hope it helps.

Good Luck !