study query

Hi everyone I want to know that till ipcc we learned and got through exams but in finals we need to understand subjects and good knowledge of things .....but we have a habit of learning so when we go to understand things we end up learning things and the outcome is nothing. and exams get a negative result everytime.....I am not able to understand what to do to improve it..I don't have practical experience as was a dummy article..... Please help....