How to setup a directory in Xcode project 16.2

the Xcode Version 16.2 (16C5032a), I want to know how to setup a directory in Xcode project when develop the iOS app. Here is the whole thing:

1. I start a new iOS App project "test_path".
2. then I right click, and choose "New Folder", to make a new folder "configx"
3. then I right click on the configx folder, and choose the "add files to test_path", add a file in it
4. But the folder does not exist in the project when try to access by "Bundle.main.urls" func.

5. when ls in the Mac, /data/Containers/Bundle/Application/E4F11903-3FAD-467F-A4CD-60AC68D64934/test_path.app, the file just at the root path of test_path.app, no "configx" folder ahead the file.

so, how to setup a directory or a path in iOS project?