WordPress Multilingual Plugin is the most popular premium WordPress plugin used for creating multilingual sites.
Chap theme does not come with this plugin bundled with the theme, but in the case that you have a license and wish to use it, the theme supports WPML plugin’s Language Switcher in all widget areas:
Header widget area
Menu widget area
Primary sidebar widget area
Secondary sidebar widget area
Footer widget area
The Language Switcher in menus is also supported in all menus: