A standalone film is like a toy that doesn't need any other toys to be played with. Just like how you can have fun with a toy car or a doll by itself, a standalone film is a movie that tells a story on its own without needing any other movies to make sense.
Sometimes, movies are made as part of a series or a franchise with the same characters and storylines that happen in different parts of the series making more sense when watched together. But, a standalone film doesn't need any of that because it tells a whole story from beginning to end all by itself.
It's like a book with only one chapter that starts at the beginning and ends at the end. You can enjoy the story without having to read any other chapters before or after it.
So, when you watch a standalone film, you don't have to remember anything that happened before or after it, and you can just sit back, relax, and enjoy the story.