You step out of a plane on water, you drown.
Well if you're making a modern AC then why not have something like the Cessna 208 Amphibious Caravan (for instance) has,
Floats with intergrated retractable gear, which is lowered from the floats.
You land on water, "sail" to shore, pop out the gear and drive onto the land.
basically it is meant for dual purpose landings, but using it like this occurs aswell, and you would also give your new plane that dual purpose with it, not restricting it to water only.
dunno bout the possibilities of creating it as such, just a thought