I do not think that you are going to find a person to write the story for you on enotes. I am not entirely certain that this is the site's purpose. For this, I apologize. Yet, I think that there is enough here for you to compose a fairly interesting short story. The lead is a good one. You are just going to have to figure out where you want to go with it. In a lead sentence like this, the creativity is already there. The next sentences can describe what the compartment looked like and the feelings you want to explore upon entering the compartment. Is the entry one out of fear? Is the subject running away from something? If so, what? Is there a sense of excitement and anticipation? If so, explore that. There are many ways to go with this. Your lead sentence drives the story and you are able to control where you want to go with this and how you want it to be. I think that this makes the story not only relatively easy to write, but fun, as well. Consider the some of the best drama and most intense moments are seen on train platforms. The people entering the trains, the people that are left behind, and those who work on the trains can form some really interesting stories and elements of writing. I think that you need to focus in on what you think would be an interesting story to tell. With this lead sentences, all you need to do at this point is simply tell it in written form.