@Pascalxd
You will have to submit your translations to http://i18n.osticket.com/, wait for them to be approved, wait for the new language packs to be built, and then wait for the new language packs to be released. Then you will be able to download the language pack with the new translations.
If you do not want to wait for the official Language Pack releases you can always research Crowdin and how to use their translation system then you can package the language using our CLI tool, and then build them yourself. There really is no guide on how to do this so you'll be on your own essentially.
Cheers.