Water is a polar inorganic compound ( H2O) ( attracts ) hence why its consider the " universal solvent" Very essential to all life on the planet from desert plants to penguins. 3/4 of the planet is water 3 % is fresh but 2/3 of is locked away as snow/ice. During the formation of the Earth 4.5billions ago, comets/asteroids delivered much of the water in two phases that we see today. Used by everyone and many businesses during manufacturing of everyday items . 1 cubic meter of water is about 1 tonne . Unlike other compounds/substances, when water solidifies, it decreases in density ( structure of it kind of lines up) hence ice floats on water. Therefore , any large amounts of ice(in the world) melting(climate change/ increase in Co2 ) will increase ocean water levels. Water on the planet carries heat/energy around the world. Atlantic currents bringing warm water from down south to a place like Europe with out this current , Europe would be much colder during the winter( for being so northern) Melting of ice would increase the amount of fresh water hitting the exchange zone/spot. Since fresh water is less dense than salt /ocean water , this heat exchange in the Atlantic would slow or stop. Basically cooling that warmer water. Water can hold quite of bit of thermal energy(heat) . I t has high specific heat capacity of 4.19 and really basically regulates the temperature of the planet. A hurricane is basically natures concentration of all the energy/heat that's within the water (near the equator). Water is used to create steam to turn generates for power in nuclear and fossil type fuels. It can store energy like in a dam to help power many homes as well.
There's many sites and videos that can go into detail more with more info and examples than this. Liquid water really makes Earth different from any other planet in the solar system. Earth isn't the blue planet without it.