You can add your own locale & translate the script to your language.
Click on the "Add New Locale" menu and add your locale & name. This will create a folder in the name of your locale at /lang folder.
You can then start translating all the files. Please make sure you don't make any syntax mistake during translation. You may get 500 error in case you make syntax error.
To improve the performance, the script caches your locale. It might be possible that your translation are immediately not showing in the script. In such case, you need to clear your server cache by running below command:
php artisan cache:clear