If you are new to darkroom, I'd advise against going THAT big. Please realize, you will be dealing with a WET PAPER that cannot absolutely be bent, creased, bumped, poked, or otherwise do anything that will mar the surface. It starts to be challenging at around 11x14, get harder at 16x20, and absolutely a nightmare at the size you want. Fiber paper is nearly impossible without extensive experience. RC may be possible.

Where are you in central Florida? I'm near Orlando. If you want to experience doing 16x20 RC, you can come over and you can try it yourself, if you like.

As to enlarger, most commonly available ones will require you to "flip" the unit and project it on the floor at that size. You'll also need some GIANT trays which aren't cheap. You are literally talking about taking it outside and hosing it down to wash!