Can you say "the" before furniture like this? If so, does it mean a specific piece of furniture of all the furniture in the room?
ex)The furniture in the room is nice.
Since furniture is a mass noun, therefore "the furniture" refers to all the furniture in the room. You use "the" before "funiture" to indicate all the funiture in that specific room/house, not a specific piece of furniture.
If you want to comment on a specific piece of furniture, you have to say "that is a nice piece of furniture", "the table is nice", "the carpet is nice", etc.
DQ