One good idea is to base a story on a unique location. For example, a forgotten island full of strange creatures. Another idea could be to create a story around a character with an extraordinary ability like the power to control time. And you can also get ideas from historical events and give them a fictional twist.
Well, you can start with a simple object and build a story around it. Say, a magical key that can open doors to different dimensions. Or think about a character who is an outcast in society and their journey to find acceptance. Also, dreams can be a great source. A story where the main character enters other people's dreams to solve their problems.
Good ideas for creative stories can come from personal experiences too. Maybe you had a really strange encounter once, like seeing a mysterious figure in the woods. Use that as the basis for a spooky story. You could also mix different genres. For instance, combine a western setting with a science - fiction element like aliens arriving in an old - west town. And don't forget about mythology. Take elements from different mythologies and create a new world full of gods and heroes.