Every Starter Kit download includes an import file for Loupely Canvas Pro alongside the HTML and CSS. It’s optional, and it only matters if you run Pro.
Import that file into Pro and the same components load as named snippets in your snippet library. From there you reuse them by name across a whole site, the same as any other snippet, instead of pasting the same block onto each page.
If you’re on the free theme, you don’t need the import file. The HTML and CSS in the download already work on their own. The import file is there for the moment you move to Pro, so the components you configured carry over without rebuilding them.