How can I start Classical Mechanics, I mean by the help of which book......
At which level?
Honours 3rd year level
BS in Physics
It is hard to recommend anything if you do not provide more information. We do not know what school you go to or what level your BS physics course is. We do not know your mathematical background. We also do not know what your interests are or what exactly you are looking for in a book that your suggested course reading does not already provide. The following are all good books at different levels. See the amazon preview and pick the one that woks for you.
Kibble Birkshire - https://www.amazon.com/Classical-Mechanics-5th-Tom-Kibble/dp/1860944353
Taylor - https://www.amazon.com/gp/product/189138922X/
Speigel - https://www.amazon.com/Schaums-Outline-Problems-Theoretical-Mechanics/dp/0070602328
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