Most of the time you would us has/ have been is when you often do something or you were currently doing something. For example, "I have been singing since I was six years old." You sing often and it's something you have been doing for a while.

*(present perfect continuous) Hi, you might consider taking some courses as the following one: https://www.coursera.org/learn/perfect-tenses-modals Besides, the best way to understand is to practice and assimilate - I suggest to search in your local Library for exercise notebooks - in alternative, you have online sites like the following: http://www.perfect-english-grammar.com/present-continuous-exercise-1.html finally, see how they're used in English texts; and memorize some examples best

Why don't you try GOOGLE?