Generally, depending on somebody else to keep you safe in the water is not a
good idea unless they are truly dedicated to your safety.  This is how
handicapped people occasionally get to dive, including the blind.  The kind
of care and attention they get, however, is way beyond what the average
diver or snorkeler would get.

I'm a former Water Safety Instructor.  I used to teach children and adults
to swim.  Adults are usually harder, but those that are truly comitted
usually succeed.  You can learn to swim, but you may not be able to learn to
swim in the timeframes you have described.

There's more to it than that.  I know divers who, without fins, are lousy
swimmers.  They say they can't swim, but that's not entirely true.  They
can, just not well.  Fins make a world of difference.  Swimming without fins
is quite unlike swimming with them.  For most swimmers, the hands and arms
are the primary method of moving in the water.  With fins, the legs and fins
are all you need and, normally, all you use.  It is generally believed that
it is more efficient to keep your hands and arms still and use your fins
only.  There's a fair chance that you'll be able to swim well enough when
wearing fins to learn to snorkel or dive, but be sure before you risk
yourself in water deeper than you can stand up in.

As to scuba diving, the answer to the first part is yes and no.  Normally,
you get certified before you dive.  There are basic rules that will allow
you to dive safely that, if ignored, can and have killed people.  Nothing
complicated, but things that must be known and done to dive safely.  The
entry level courses teach these rules plus assembly and use of tanks,
regulators, buoyancy compensators, etc. and a few very basic skills you are
likely to need sooner or later, things like clearing a flooded mask
underwater and adjusting your buoyancy.  There are so called resort courses
that do not result in certification.  You get minimal, but essential,
instruction, a bit of practice with mask, fins and other equipment, and then
get to dive under close supervision (hopefully) of somebody trained to
assist the very inexperienced.  Most certified divers find these resort
courses to be a bit on the risky side, but a lot of them have been done
successfully.  In your case, your lack of swimming skills probably adds to
the potential for problems and the likelyhood of panic should you have one.
In my personal opinion, you'd be pushing your luck, but it's your luck to
push if you chose.  If you try a resort course, pay close attention to the
instructions and make sure you understand them fully.  Pay particular
attention when you're told not to hold your breath.  Pay a lot of attention
to the ratio of dive supervisors to guests and how your instructor responds
to questions.  Consider what will happen if more than one guest has a
problem at the same time.

I prefer a slower approach to diving, starting with swimming, progressing to
snorkeling and then moving on to diving.  Instruction can help you learn to
swim and to snorkel.  It's pretty much necessary for diving.

In my previous post, I suggested you find a way to be in the water safely
without assistance and then pursue your goals with assistance.  I was hoping
you'd come up with your own ideas.  Figuring it out for yourself is usually
a more effective way to learn than hearing it from somebody else.  One way
is what is called a snorkel vest.  It's an inflatable bladder that you wear
over your head and strapped around your waist.  Most can be inflated orally
or by CO2 cartridge all of them are designed to help keep your head above
water.  They are required on most snorkeling boats I know of.  Having one
and knowing how to use it effectively, are not the same.  A weak swimmer
should consider wearing one anytime they're in the water and, for that
matter, wearing something to serve the same purpose any time they're on the
water, including when they are in a boat.  To be effective, you have to have
a flotation device handy when you need it.  The best way to do that is to
wear it.

If you can master using a mask and snorkel and purging both while in the
water as well as propelling yourself around with fins, you can probably
snorkel safely.  Practice in the shallow end of a pool until you're
comfortable.

Lee

Perhaps you're right.  I was swimming before I can remember and I'm a Pisces
from the right coast.  I don't think I've ever been 26 blocks from the
ocean, but I've never lived more than a half hour from it.  I compensated by
having a pool and/or lake in the back yard.

Lee