Dear Aspirant,
the best book recommended by students for general for UPSC exam is General Knowledge by "Arihant", "Disha" and "Pearson". The best way to prepare for you current affairs part of UPSC is by reading the newspaper on a daily basis.
With respect to building confidence, solve as many previous years papers as you can, it is a great way to boost your confidence. Also believing in yourself is equally important to develop self confidence.
Now when it comes to preparing for SSB interview try and follow these given steps :-
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