One idea could be to create a story about a clumsy magician. The magician tries to perform simple tricks but everything goes wrong. For example, when he tries to pull a rabbit out of his hat, a whole flock of chickens come out instead and start running all over the stage. He then tries to make a flower appear, but instead gets a cactus that pricks his finger.
You might consider a story centered around a mystery. Maybe a disappearance or a crime that needs to be solved. This can keep readers on the edge of their seats as they follow along with the investigation.
How about a story where a clumsy wizard accidentally turns his own hat into a living, talking creature? The hat then starts giving the wizard advice on how to be a better wizard, but it's all really bad advice, like using a broomstick to stir potions instead of a magic wand.
Imagine a world where people can exchange their dreams. A person who is always dissatisfied with their own dreams decides to trade with others. But they soon realize that each dream has its own problems and that the grass isn't always greener on the other side. Through this experience, they learn to appreciate their own dreams and the unique experiences they bring.
One way to write a fantasy fiction story is to start with a prophecy. For example, there's a prophecy that a chosen one will be born with a special mark and will defeat an ancient evil. The story could follow the journey of this chosen one as they grow up and discover their powers. Or, you could create a world where dreams are real and people can enter other people's dreams. A thief could use this ability to steal secrets from the rich and powerful. Additionally, you could write about a group of adventurers on a quest for a lost city full of treasures and magic.
Set it in a different time period like the 1920s. Cinderella could be a flapper girl who dreams of going to the big jazz parties but is held back by her step - family. The 'prince' could be a rich jazz musician. Instead of a glass slipper, she might leave behind a beaded headband. And the fairy godmother could be an older, wise jazz singer who gives her the confidence and the right look to attend the party.
You can get story ideas by observing your daily life. Simple things like a conversation you overheard or a strange event you witnessed could inspire a story.