Hi alamin,
All of the static labels/strings that appear on the front end of this plugin are localized in the code. This means they are ready to be translated and can be found and identified as such by any translation plugins (e.g. WPML). Information on creating a translation can be found here: https://doc.fivestarplugins.com/plugins/restaurant-reservations/user/labelling/translating
For the translations to appear on the front-end, the WordPress site’s language must be set to that same language locale.
All of the translations are user-submitted and not done by us. If there is an issue with the specific translation, you can submit your recommended changes to the community translation.
https://translate.www.ads-software.com/locale/fr/default/wp-plugins/restaurant-reservations/