You have a data source that contains 20 tables.

To organize the tables in the Data pane based on the type of data contained within the tables, you should use folders. Folders are a way to manually group fields, parameters, sets, or tables in the Data pane according to your preference. You can create folders by right-clicking on the fields or tables you want to group and selecting Folders > Create Folder. You can also drag and drop fields or tables into existing folders. You can name the folders according to the type of data they contain, such as sales, customer, product, etc. Folders can help you find and access the fields or tables you need more easily and efficiently. References:

Organize and Customize Fields in the Data Pane - Tableau

Tableau Certified Data Analyst Study Guide