Hi, could you please tell me what should I improve to get a 4 at least??? Thank you very much.
Getting from a "3" to a "4" is difficult enough that I can't explain it all here. I'd have to teach you some skills that would require time and study on your part (not to mention mine).
The most pressing problem is this:
When I look at your essay from a distance on my old-school computer screen, I can see the word "education" (and other forms, such as "educate" and "educational") so many times that it almost jumps off the page.
I didn't even have to read the paper (although I did read it) to know that it was a three. One word or idea so deeply pervading an essay reveals problems in every important area of writing: organization, vocabulary, and grammar.
Over the years I have sat in many GRE (and GMAT and SAT and AP) reading rooms. You don't want to give the reader a reason to skim your paper, slap a score on it, and move on to the next.
There were similar problems with other words and phrases.
The good news is that your paper can't be a two because it attempts to answer the question and because your mechanics are generally strong. I realize that you'd like a six, but at the very least I can almost guarantee that you'll score at least a three on the test.