It's often easy to become sidetracked by the players who come and go in your story but who don't really do enough to move the action along to justify giving them much play.
The questions you might ask yourself are:
- From whose point of view am I telling this story?
- Should the POV character (the one telling the story) be the same as the protagonist or 'star' of the story?
- Who is the protagonist?
- Is there an antagonist? (Hint: Neither protagonist nor antagonist have to be people, but for beginning writers it's best if they are.)
- What does the protagonist want?
- What does the antagonist do that prevents the protagonist from getting what he/she wants?
- How does the protagonist overcome the obstacles placed in his/her way by the antagonist?
Choose your hero, his enemy, and a few allies for both sides. Your POV character might be one of these allies. Or it could be a third-person narrative, where the POV comes from the narrator. That's tricky writing, by the way, so again, for beginning writers try to choose a POV character who is likely to be on hand for most of the events in the story.