When first created, your local WordPress.org site will have an interface and backend in English. To have the pages and the Dashboard in your own language, you will need to translate them on Trasnlate.WordPress.org in the same way you translate WordPress itself.
Translating the Forums works the same way as translating the Rosetta site. If you want your local forums to be in your language, you will need to translate all the strings in the Local Forum project and the string in the bbPress project
Screenshot of the Local Forum project on Translate.WordPress.org
A screenshot of the Local Forum project for Pashto
The translations of the interface of your local site get deployed automatically once every 24 hours (once per day at 23:00 UTC). After you’ve translated the Rosetta project to 100%, wait for the automatic deploy to see them on the website.
Some pages like “Downloads”, “Install”, “Contact” and “Releases” can not be translated from the backend of the website. Instead, all text in those pages is available for translating in the Rosetta project and will be localized once Rosetta is deployed.