What do you need to explore the ocean?

It depends whether you are in a liferaft or a boat, and what climate you are in, as exposure is your number one enemy. Once you are protected from sun and wind, as long as you are in an area where cold is not your enemy, we turn to water. You will need a means to get fresh water - boats and lifeafts should be equipped with a freshwater maker (can hand-pump an osmosisi type for a few people) or a solar still (its effectiveness will depend on climate/environment). Next you will need food, with fishing being the most likely source. A boat or liferaft expecting to be at sea with survival in mind should have a small handheld fishing reel and line (there is a round plastic one referred to as a Cuban yo-yo) with hooks. Catching the first fish will be the hardest, due to lack of bait.

Now, you can survive for months at sea.