English into Dutch.
In the directory where you installed MediaWiki, in the same directory as index.php and api.php
Ah, OK. In that case, look around in your public_html directory or whatever it's called, and try to find the MediaWiki files.
I don't have FTP access to your server, and it's not possible to find it via the web.
I can't tell you what to do beyond what I've already told you, because I can't magically look at your server's filesystem. You'll have to FTP into your server and browse around to find LocalSettings.php (or other files related to MediaWiki).