1) the first is to use the Database with a column for each language example: language (id, fr, en, ar, de; it) and compare each word with a translate function ($ wordfrancais, $ ln)
2) the second method use a JSON file for each language or fr.php en.php file
$ lang = array (
"Would you like to overwrite or duplicate the following:" => "Would you like to replace or duplicate:",
"Prefix" => "Prefix", ......);
3) use Website Internationalization plugins for example I18n