Board Thread:Support Requests - Community Management/@comment-36579093-20190527221315/@comment-9605025-20190528185716

Yes, the editing interface always shows you your preferred language regardless of the wiki's language. Also, the English spacial pages are always aliases for the non-English versions. So, for example, Special:Contributions will always take to to that page or whatever the equivalent is called in the wiki's language. I believe (but am not entirely sure), that MediaWiki pages are always in English regardless.

About the only time you need to worry about the wiki's language is when creating page content and naming pages (including templates). - Edit:

You can always direct users to Help:Contents. From there, they can explore the many help pages; most of which should be sufficient for them to get the basics down.