Hi Maartje,
(I’ve moved your question to a new topic, since it’s fundamentally different than the original)
Have you taken a look at Jono Bacon’s excellent getting started guides?
- Getting Started with Discourse - Part 1: Discourse Setup
- Getting Started with Discourse - Part 2: Discussions and Trust Levels
- Getting Started with Discourse - Part 3: Admin and Analytics
Part three is the one you need, but I suggest you start from the beginning, to get some understanding of the fundamentals 