If the language drop-down is bothering you, you can disable it. You need to be an Administrator to perform this action.
In the Confluence Administration, go to "Manage apps". Log in as an administrator.
Click on "Language Macros for Confluence" to expand the settings.
Click on "xx of yy modules enabled".
Scroll to "Languages dropdown Web Item" and click the "Disable" button.
Also, disable "Languages Dropdown Web Resources".
Return to your Confluence page. The drop-down does not appear anymore.
Disabling the drop-down means you will have to change the language manually by editing the page's URL, see How to change a page's language with a query parameter.