A disease or infection is caused by a virus or bacteria. For example, covid-19 and colds are viral. Bladder and pneumonia are examples of bacterial infections.
Both a viral and bacterial infection can sometimes heal on its own. But when people get very sick from a bacterial infection, antibiotics can save lives. We have good and bad bacteria in our bodies, both of which are attacked by the antibiotics.
Those pills have no effect on a virus. It is therefore not wise to fight your (good) bacteria if you are sick with a virus, because it does not help against it.
If we take a lot of antibiotics, a bacteria can become resistant. Then antibiotics no longer help against that bacterium, and you can therefore no longer fight diseases caused by that bacterium.