I am inetesting in writing story, my problem is i have idea but cant convert it in to a story.How I can do it?

take a pictur and do picture reading. Try formatting words in your mind. If this doesnt help, Write a story without any help and however you feel.Then show it to an elder person to point out your mistakes. Try to improve them. You must have good imagination to write stories. Then you can become a good story writer. I am 10 and I write stories. I request you to choose my answer as the best cuz i have never recieved my answers as the best.I have tried to help you by answering your question

I suggest you start by writing an outline of your story. Just jot down what you want to get across to the reader, and what events you think are important. Then, write according to your outline.