Can you get sick by being near a sick person who is merely talking or exhaling, and what if they don't appear to be sick yet, but are carrying germs?

Contagiousness: Most common germs that make us sick are viruses that are passed from person to person, often on our hands. There are some germs that are airborne or in tiny droplets. But sitting near someone who isn't coughing or sneezing directly on you shouldn't get you sick, as long as you don't touch your own face, nose, lips, etc. to avoid carrying germs from the sick person to yourself. WASH YOUR HANDS!

Highly unlikely: There are many types of infections: bacterial, viral, fungal and parasitic. Most of these can't spread through the air. Some bacteria and viruses may spread through the air but usually from the sick person coughing or sneezing, not just breathing. We are all exposed to many germs in our environment every day. The main determinant as to whether we get sick is our immunity/resistance. See comment: