These buttons on our demos just examples of how real languages and currencies switches can be displayed, they do not work, by default.
To add switches, that work, you need to install and configure additional plugins.
For example WPML or Polylang or qTranslate or similar https://wordpress.org/plugins/tags/multilingual/ . Then follow plugin documentation to translate the theme.
Multi-currency for WooCommerce plugin https://wordpress.org/plugins/woo-multi-currency/ or similar.
