Absolutely! I personally and another member on here as mentioned, don’t be flying over any body of water on your first time out until you’ve mastered the basics on land.
Depends what height you’re at. I’ve kept up with some very fast moving vessels at less than 100 feet on the Solent - and a headwind has also factored into it.
Yes, but you’ve been operating from dry land. I wouldn’t want to risk my drone flying from a boat or a ferry, especially not with collision with the boat/ferry being a possibilty below mast-top height. Just too chancy for my taste.
I’d fly a kite from a ferry.
Dry land or not, it’s still not impossible to carry out when a vessel is travelling at 18 knots.
Not disputing that, but flying from said vessel into a 20kn headwind and having to chase it like the OP is suggesting would be a lot more risky than flying past it from a land-based home point.
Without the OP proving more information on the type of boat and planned flight, bouncing opinions about is tending to go around in circles.
Let’s wait and see what he says when/if he posts more info.