Technically, the instructions say to write a story, so it should contain all standard story elements: characters, setting, and a plot that includes a conflict and a resolution.

But in practice, your judges are instructed to pick the character they like the best, and there are no rules around what it should contain. If you fail to include a conflict and resolution, you won't be disqualified. Your entry is just likely to be less compelling than it would be with a conflict.

Cheers,
Michelle