The simplest way of exporting your notebook is by creating a PDF. You can either save the PDF to your device or print the file to be able to read and use it independently of your device.
Open your notebook settings by clicking the notebook cover in the navigation panel on the left side of your screen. Then scroll until you see export options. Press "Print".
In the following, you can adapt the PDF to your liking. Click "Generate PDF" to create the file.
Click "Print" to either download the file or print the document on paper.