Undergraduate / "Satisfy" -----describe the world you came from [NEW]

Prompt #1 (freshman applicants)
Describe the world you come from - for example, your family, community or school - and tell us how your world has shaped your dreams and aspirations.

Everyone has his own life story, and this story is strongly affecting his future. Regardless rather our past is glorious or not, it is most important to know how to cherish and satisfy what we have in our hands because when we are complaining about life, there are people in this world wishing to life in our lives. As I am growing every day, I figured out a life lesson from my past. My story will begin from when I was just a three month baby. My mother went to Singapore, after I was three month old, to find a stable job. In the four year that my mother was in Singapore, my father was constantly on his business trip, thus I was left with no choice but to live with my grandmother and grandfather. When I was four years old, both of my parents came to Los Angeles to find a better life and hope to give their daughter, me, a brighter future. Even though in the next eight years I lived the life completely without father and mother, and in my childhood memory they were just a blurry image, but with my grandparents' company I never fell lonely. My grandparents taught me how to read, write, sing, and draw, etc; they always give the best to me such as food, drink, and education. As time flies, eight years later, I was twelve; I left my dearest grandparents and reunited with my mother, separated for twelve years, and father, separated for eight years. At first, I frequently argue with my parents for such little things. I was desperate and lost; the only one I can think of to get help was my grandparents. They patiently taught me many life lessons. I find out that I was never satisfied with what I had. Eight years ago, I did not cherish with the days with my grandparents, thus sometimes I made them angry; eight years later, I did not cherish with the time I spend with my parents and did not try to understand them better, thus there was lots of contraction between us. For the next five years and even now, I've always keep "cherish" and "satisfy" in my mind to keep me strongly bonded with my family and friends. In this life lesson that I learned for my past, my find what I want to learn and what I want to major. Environmental pollution is one of the biggest threats to the Earth, thus I want to major in environmental policy to do something for our society and purify our Home.

Can anyone please help me fix this essay, my grammar is terrible. Any sort of comment, or criticism, would be helpful! Thank you thank you!