Using one of the templates or forking an existing project will get users up and running in no time.
If you press the "+ New Project" button in the header over there ☝️ you'll be presented with a selection of templates organised by technology. These range in complexity and are a great place to start a new project from. You don't have to be logged in to create a new project, but you will if you want to save any changes.
Pressing the "Fork" button will make a copy of the current project at the currently selected point in the project history. Again you don't need to be logged in to do this, though you will need to before you can save any changes.
Please note that when you do fork a project it won't copy the history, but there will be a link back to the source project for your reference.