Illte - that is the principle behind so many of the rules that have been made around the virus. It floats as droplets in the air when someone who is infected (even if unknowingly) breathes out. Those droplets land on every surface: light switches, computer mice, door handles, table tops, computer keyboards, food on supermarket shelves - just everything. That is why we are told to wear masks - not to protect ourselves, but to stop the wearer breathing out the droplets and directly infecting another, and also these droplets landing on places that others will touch. If they then touch their mouth, nose, eyes the virus can get into the body and infect the person.
Someone does not have to cough to create droplets. All they have to do is breathe! Coughing just spreads the virus further.
It is also the principle behind handwashing, so that if someone touches a surface with droplets on they can wash the virus from their hands.
Sorry to sound a bit basic - but I was surprised that you were not aware that the droplets land on furniture - on everything really!