Moderator is entirely correct. Here's the deal, you can die trying to breathe underwater. If NOT dying is important to you, take a scuba course. Its fun, you'll learn what you really need to know, you'll meet interesting people, and you'll end up qualified to rent equipment or join that once in a lifetime group for a tank dive in a spectacular location you may never visit again.
Bottom line, and I don't care whether its diving, flying, or jumping, if you're going to risk your life, do it after getting the best professional training you can get

Take it from me, you'll live a lot longer and have a lot more fun.
seer