Write the essay telling a story from your life, describing an experience that either demonstrates your character or helped to shape it.

Write the essay as a personal narrative

Use these rules: Rules and Tips for writing a personal narrative.
https://grammar.yourdictionary.com/grammar-rules-and-tips/tips-for-writing-a-personal-narrative-essay.html

How-to-guide to writing a personal narrative.
https://www.thoughtco.com/how-to-write-a-personal-narrative-1856809

Examples of contest winning personal narratives.

The essay prompt is : Tell a story from your life, describing an experience that either demonstrates your character or helped to shape it.