One idea could be 'The Lost Key'. It can be about a character who loses a very special key that has the power to unlock a mysterious door in an old, abandoned house. The search for the key leads to unexpected encounters and revelations about the character's past.
I would recommend 'The Castle' by Franz Kafka. While not strictly an anarchist novel in the traditional sense, it shows the absurdity of a highly bureaucratic system which is something that anarchists oppose. The protagonist's struggle against the faceless and often irrational power of the castle can give beginners an idea of the anarchist dislike for overarching authority.
Begin by brainstorming. Write down all the ideas that come to mind related to your story, no matter how crazy they seem. Then, choose the most interesting ones. Next, think about the basic structure. Will it be a linear story or have flashbacks? After that, start creating your characters. Sketch out their appearances and personalities. Then just start writing, even if it's not perfect at first.
For beginners, start simple. Pick a familiar setting, like your hometown or school. Then, think of a basic story idea, like a lost pet or a friendship problem. Don't worry about making it super complex at first. Next, just start writing. Don't stop to correct every little mistake. Let the words flow. After you've written a draft, then you can go back and look at grammar and spelling. Also, read other stories in the genre you want to write in. This will give you an idea of how the stories are structured and what kind of language to use.
First, come up with a unique concept. It could be inspired by your own experiences or something you've always wondered about. Then, decide on the beginning, middle, and end of the story. Don't worry too much about making it perfect at first; you can always revise and improve as you go along.
Start with a simple idea that interests you. Outline the main plot points and characters. Don't worry too much about making it perfect at first; just get your ideas down on paper.