Writing an astonishing story is difficult. You would have to be committed to writing your story, as well as putting maybe months into it. It can also be trial and error. Example: You might make a story that you are satisfied with, then it turns out to not be so great. You have to learn from mistakes. Go slow, then eventually you might take off from there.
Steady advice can be gained from asking other writers/members for tips or advice. Alternatively, there are articles in the Help & Info page, that provide ideas and experience from others.
Maybe this helps?