This is possible only when you practice. Refer NCERT and solve questions. If you go on looking solutions then it won't help you. Try to solve questions and know why it is done like that. Why it has to be done like that. If you throw questions on every thing you get to know , you will see the reality.
There are many parts which has theories also. You can read them and solve as many as numericals from which ever part feels good to you.
Hope it helps
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