Hi Adel….I’m not familiar with that plugin “Polylang”, but at first glance, it appears you can put that code into any location in a theme’s template. For Circumference, it’s really up to you to decide where in your page (site) you want this to display. Also be aware that if you are adding new code to a theme file, I hope you are using a child theme instead of the actual parent theme itself. If you modify a theme file without using a child theme, and there is a theme update, you will lose that custom change.
If the plugin has a widget or shortcode, perhaps putting into the “Announcement” widget position is ideal.