What Would You Do With A Time Machine?

Hello there good morning
          Fine morning here, let me start your day with a thought.
           The grand essentials of happiness are: something to do, something to love, and something to hope for.
            So this question is being bugging me from many years, what would happen if someone would have built a time machine? Would all the great people whom I couldn see give me a chance to say hello and shake their  hand, would it be possible for me to see the Renaissance?
              If that is way too much to ask atleast would it help to atleast go back 6 years back in time , and change my marks in a exam in which I got low GPA or could I born as a dog instead being born like this!
             So million people in this world would have million wishes to make if  such a machine was there today, next we believe in fortune tellers who are, supposed to predict our future but to be frank I don't believe in them as they are too smart for me to just flatter me about my future and earn that extra buck,or the the people who say they read it by just seeing my hand and they call it palm history.
         
  The reality
               Time machines if at all are existing or existed before in any of the mythologies in the world which I am not aware of would be nice but we know in  reality it is not so, and the way I look at it,is there a need for such a machine, if we are on time in life, and make time a horse which you can control rather than allowing time to be your master and you being its slave?
            We all have all the time in this world to think, act and do what we want but half the time we do not know how to use our time in a valuble way this word valueable has a very deep meaning it is not, just a generic meaning that your time is your time and you cannot even think about giving it to others, no it means you have to give yourself time no doubts on that, next give it to your family, next would be your friends and the last and the most important this society.
           Help this society till your clock stops help the people in suffering, teach some good words to the fools  whom you come across, the people who are always in a wonderland called egoism and if you start,doing this from an young age I think you would have no regerts and won't even get thought about that machine which takes you back in time or the future.   Good day people till next week good luck and good bye.