An acoustically "dead" room is easy enough to achieve.
Lots of thickly upholstered furniture (fabric-covered),
curtains, pile carpet, etc. will absorb reflections.
Then, before you record anything important,
make a test recording of the "silent" room for five minutes or so.
Play it back using fully enclosed headphones.
You will probably be surprised by how much noise there still is,
but there is no practical way to eliminate all of it.
Refrigerators, aquarium air pumps, lawn mowers, leaf blowers, traffic, and other stuff
often appear in the background of otherwise good home recordings.