Volunteer as crew for cruisers making passages. There are numerous resources for that, such as the one here. I'm sure the World ARC
provides that service
to it's subscribers as well, perhaps in the form of a forum section.
You'll gain a good bit of experience doing this on everything from boat outfitting, provisioning
, life at sea, as well as general seamanship. Nothing beats direct experience for learning
Then start chartering when you're comfortable with it to build your base of experience and knowledge.
Both routes will also give you some direct experience on different boats that will allow you to better evaluate your own needs and preferences leading up to buying
a boat. While it's fun to contemplate different boats, thinking about what boat you're going to buy now is a bit like deciding on what car you're going to purchase
when you don't even have your learner's permit
Don't worry about piracy
. There are ways to remain safe, or at least decrease your chances of it being an issue for you to where it's less than the risk of being hit by lightening. Put another way, there are many, many more risks to life and limb when circumnavigating that are of greater concern as far as preparations and planning go than piracy.