Given that 75 percent of earth’s surface is covered with water, why is water considered a scarce resource

Not much of it we can use

Explanation:

3 percent of earth's surface water is fresh water and furthermore, 2.6 percent of this fresh water humans do not have access to.

not all of the water is drinkable

Explanation: an alarmingly small percentage of the earth's water is fresh water the majority of the water on earth is salt water.

if you're asking what comes out, it's steam.