A page is a Markdown file in your Space. Write notes, add links and tasks, and optionally add Metadata. A page named Photo Walk is stored as Photo Walk.md in the space folder.
Start with Guide/My First Markdown Page for a writing exercise.
Page names are relatively free-form, but have to adhere to a few Names#Rules.
Your Space will contain two types of pages:
Library/, including your configuration page ^Library/Config. A lot of these will be part of Library. You navigate between these using the Tool Page Picker.