An infected person can exhale virus in a droplet, which is large and hyperbaric so heavier than air
or as an aerosol which is simply smaller and hypobaric so it floats on the air
droplets are the majority but have a range of only a few feet. So if you are standing within that range the droplet can get on your face or even in your mouth or nose
but most droplets fall on the floor or another surface where they are called fomites
touch a fomites with live virus, then touch your face, and you may be infeccted