Comrades, what do you use to set up those things for the hut floor in Monster Hunter World, which currently only has fish and a rabbit?

It's just these little critters like rabbits and fish. There are a lot of critters you can catch, basically any non-hunting object you can see that moves, and different maps have different environmental creatures. There are some environmental creatures that can only be caught at certain times of day or in certain weather and locations.

Catching all kinds of rare critters is also a great source of joy in the game.