The most reliable way to save the story text as a .txt file is to highlight the text on the fundraiser page, copy it, and paste it into a text editor (like Notepad or TextEdit) and save it.
GoFundMe does not have a native "Download as .txt" button for campaigns, but you can export donor data and use other methods to save the campaign text. How to Save or Export GoFundMe Data
If you are looking for a specific story from a campaign, I can help you locate that specific GoFundMe page if you have the name. If you tell me:
If you are the organizer, you can export a report of donations, including donor names, amounts, and comments, as a .CSV file .