Minjucks is intended for small design-heavy static sites, e.g. a portfolio or a product landing page. If you want to build a content-heavy site, consider using a different static site generator that is more suited to that purpose.
Minjucks uses Nunjucks templating, which is easy to learn. Minjucks also supports YAML frontmatter in pages, using gray-matter).
PostCSS is included for styling, but you can use plain CSS if you prefer. It is being used here to import stylesheet partials, so that only one CSS file is generated for the entire site. CSSNANO is used to optimize and minify the CSS output.
Browser Sync is included for development, which provides live reloading and a local development server. It also synchronizes interactions across multiple devices, making it easier to test your site on different screen sizes and browsers.