Hi guys and gals,
So, I'm just getting started with sailing. Ie, I'm taking my first lesson soon

I've been reading everything I can get my hands on, so I'm pretty excited.
I have at least a million and a half questions
I live right by a lake (Prien Lake, in Lake Charles, LA), so from our lake we have access to the ship channel which brings you right out to the Gulf, and we also have great access to the ICW, etc. Ideally, we would like to be able to eventually sail from our lake either down to Mexico or around Florida, and eventually to the Bahamas (on a very long trip.) My point is that we aren't just going to be stuck in a lake, we want to actually make fantastic voyages.
1. Knowing this, how do you proceed with learning to sail? I know I will start out on a little Sunfish or Hobie, but once I have learned well on that, do you just go out and buy a 35+ ft boat? Or would I buy like a 16 foot and then try to master that? Would a 35+ ft boat be impossible for a person who had only learned on a tiny craft? Does it matter if I learn on a boat with one or two sails? Is there a big difference in the way they run?
2. I'm fascinated at the differences between a monohull and a catamaran. I like that a catamaran is so wide and there seems to be more space up top. But I keep reading that catamarans are huge pains in the rear if you are at a marina. Why is this? Catamarans seem more expensive too.
3. Sorry I have to ask: if you're a cruiser, and you're spending a lot of time in the boat, where does your body waste go? Does it store in the boat or do you shoot it into the water?
4. Same question for trash: do you guys toss your trash except for plastic?
5. I've noticed some boats I've looked at have a rudder that you steer with a long stick, and some boats have the steering wheel that controls the rudder - what is the terminology for these two types of boats?
6. Running the ICW great loop would be great fun - is there sufficient wind, etc, to keep you going the whole way?
7. If you are sailing along a coast, how far from do the coast do you usually stay? Ie, if I cruised down my ship channel and wanted to work my way along the coast to Mexico, do you just stay a few miles out from the coast?
Ok I don't want to ask too many questions

I'm very interested in this, and I thank all of you super experienced sailors in advance for sharing any insight you have.