I am having trouble writing an essay using a flow chart. Can anyone help me, or give me advice on how I should work with this?I have my thesis, but...

I suppose my first question for you would be: "Is there a reason why you have to use a flowchart to organize your writing?"  Unless you have to for some reason, I would consider another organizational tool. Flowcharts are generally used to demonstrate a process. They show the steps that are taken to achieve a goal, or (like a "Choose Your Own Adventure Story") they show the result of different choices that could be made.  Based on your thesis idea I don't see that a flowchart style graphic organizer is going to be of much use to you.

Much better, in your case, would have been a standard Star, Cloud, or Spider diagram. Of course, these are mostly useful when developing your thesis statement and the points you want to illustrate. You already have passed that step.  Your goal now is mostly in organizing what you are going to be writing about.

In your case, you want to write about the song "Question Existing" by Rihanna. Your perspective seems to be that you think it is a good song.  This, though, is not a very strong statement.  It is enough to go with for an essay, but probably a real snoozer of one.  You need a bit more "punch."  Try something like this: "The lyrics of the song 'Question Existing' by Rihanna set a good example for today's young women."  In this example, you would quote examples from the lyrics that support this thesis.  You would need three examples from the song (one for each paragraph of your essay) and you would spend each paragraph explaining the meaning of the lyric.

Don't like that one?  Try this: "The lyrics, rhythm, and tempo of Rihanna's song 'Question Existing' blend together to form an example of excellent songwriting."  This is more in line with the spirit of your original thesis, but personally, I would shy away from this one.  Unless you have an extensive background in music, quantifying and explaining terms like "rhythm" and "tone" and "tempo" can be very difficult.

So, in short, my advice to you would be to ditch the flowchart as an organizational tool and focus your thesis on an aspect of the song that you can easily discuss.  Best of luck to you, and let me know (or post another question) if you need more help!