Tbh the wiki article for event modding is not that useful. It's one of these articles which are outdated almost everytime. To learn the event mechanics I reverse-engineered vanilla events and played with the mechanics. Well, for the basics the wiki is okay to find the key words you'll need. Then you can search for them through the files and c&p to explore what they can do and cannot do. Fortunately the mechanics are dynamic and can be used for simliar goals in other contexts.
So I endorse you to discover the vanilla files like Mitchz95 said.