Question

how is high compressibilty property of gas useful to us

Answer 1

The gases have high compressibility. This property is used in the following situation:
(1) LPG (liquefied petroleum gas) is a fuel which is made up of petroleum gas. On compressing this petroleum gas it forms liquid.
(2) Oxygen cylinders in the hospitals have compressed gas filled in it.
(3) CNG (compressed natural gas) is a natural gas, methane, which is compressed and used as a fuel in vehicles and at home.