If you have story ideas, make plans for the beginning, middle, and end, character profiles, and notes on the world, lore, etc. Then write the first draft. The chapters might be all over the place, the writing quality will need editing, but the first draft will be done. Then read it through; perhaps you'll come up with ideas for more scenes or feel you want to change things. When you've fixed those and organised your chapters, you'll have your second draft. When you're happy with what you've got, it's time for editing, tightening up your writing, and making final changes. Then you'll have a story!