I have no upper toolbar on my version. It should have the “file, edit, view, camera, draw, tools, window, extension, help” tabs don’t seem to exist.
If you are using SketchUp for Web you are correct. The interface differs from the desktop editions.
SketchUp for Web has it’s own User Guide for the interface.
For modeling operations and use of tools, you can still refer to the main desktop edition User Guide.
Suggest you make some browser bookmarks to the Help.
Also in the web edition, there is a button on the status bar that can lead to help and tutorials.