Covid-19 is a human coronavirus which can cause infections of the nose, throat and lungs.  It is most commonly spread from an infected person through:
respiratory droplets generated when you cough or sneeze
close, prolonged personal contact, such as touching or shaking hands
touching something with the virus on it, then touching your mouth, nose or eyes before washing your hands
Current evidence suggests person-to-person spread is efficient when there is close contact.