Right-click any folder in Finder and choose Publish with moss. If the folder has markdown files, you already have a website. If it's empty, moss opens the editor so you can create your first page.

Every .md file becomes a page. Every subfolder becomes a section. index.md in any folder becomes that folder's page.

my-site/
├── index.md        ← your homepage
├── about.md        ← /about/
└── posts/
    ├── index.md    ← /posts/
    └── hello.md    ← /posts/hello/

Images, videos, and notebooks go in the same folder — just reference them from markdown and moss handles the rest.