Define “do” and “novice”. Lots of them are pretty much impossible for a complete novice.
Just to talk about those I have a clue about, if by “do” you mean getting through all the gates, then you need to be semi-expert to do the canoe slalom – I could probably manage that, but then I was at one point in the top 50 in this country, anybody much below that level wouldn’t. If you’ve never paddled a racing boat before you wouldn’t even make to the start line in a sprint kayak (and I imagine the same goes for the rowing) – though I could quite competently take part in that despite being nowhere as good as I was at slalom. I guess for the sprint kayaking, you’re probably talking about weeks to months of training to complete the course in the boats they use, for the slalom, years.
Windsurfing – well it’s going to take you a while to get to a point you can stand up holding the sail, but you’ll still be falling in at every turn.
Horses – I’ve galloped on horses, I don’t think I’d even make it over the first jump.
Stuff I don’t know about:
BMX – they have gaps don’t they? Not sure I could complete their course despite almost being capable on a bike.
Pole vault!!!
Gymnastics – got to be quite tricky to do anything with some of those bits of kit they use