>>1272514Start with sailing basics. Small craft like a sunfish will teach you a ton of transferable skills and be a lot of fun. In fact, you can do this even if you don't have any ability to get formal training at all. Small craft experience and a lot of reading will teach you to sail.
Moving up to a larger boat, like a small cabin cruiser around 21 feet, take it on weekend overnights in a local lake. You'll figure out what you need to be comfortable on longer stays.
One you start playing in the ocean, realize you've kicked it up a notch. You might day sail or overnight sail four months or years before you encounter the shitstorm from hell that's going to make you never want to sail again, but remember that could happen any day, and will happen when you least expect it. Don't set out for any ambitious trips without experience and preparation.
Beyond sailing skills, you need to work on prepper/survival type skills. Preparation without skills will give you a bad day. Read up on the kind of terrible scenarios other prior have run into, and mentally prepare yourself for how you're going to handle it when any given piece of equipment fails completely. What happens when you have a bad storm and get your mast snapped? If you lose stuff to water damage or overboard? If you get sick or injured? Communications or navigation fail? Electrical failure? Fire? This stuff happens.
Not to discourage you, but if you plan any offshore sailing, be ready for the worst.