In the tutorial, readers are guided on building a Retool app to import CSV files into a Firestore database, offering insights into working with common data-sharing formats. The process involves setting up Firebase resources, configuring queries for data insertion, and creating a user interface with Retool's components like file buttons and tables to visualize and upload data. Users are taught to handle individual CSV rows and are introduced to a method for uploading entire files, albeit with caution for large files due to potential memory constraints. The tutorial also highlights the utility of Retool in streamlining processes, suggesting broader applications beyond the scope of the project.