there needs to be some sort of chimney....and the smoke will go up the chimney.
as for the wood and real well dried wood should work well....never burn anything green or any type of garbage as the residue can cause chimney fires.
Absolutely not. Vent free means the spent fuel vents into the house.
Is it designed for burning gas or propane? If so, you absolutely cannot burn wood in it. I have no idea what a "vent-free woodstove" is.
Where does the smoke go in a ventfree stove?