Humidity indicated by a number is the relative humidity and it’s a measure of how saturated air is with water. Air can carry a certain amount of moisture in it. At 100% relative humidity, any additional moisture can’t enter the air and has to remain as water. Fog is a good way to think about 100% relative humidity air, where the air can’t quite hold the moisture.
So, 100% humidity means that the air is currently holding the maximum amount of water possible for its current temperature. If the air was to cool down even slightly, it would be forced to give up some of that water vapor and it would condense into droplets.
If a sponge is 100% saturated, so that it can old no more water, is the sponge now made of water? The in the same way, 100% humidity does not mean that the air turns into water.