If you are new to photography, check this list of videos
If you just need to know how a wedding works, start shooting all your friends.
This is how you interact with real people and understand lots of things.
About technical details: get a dedicated flash, spare batteries (for camera and flash) and a good light objective (F1.8 - F2.8). Also, you should have a wide objective 18mm or max 35mm (to get small spaces in a single picture). Also, not an expert wedding photographer but, I had some experiences.