Hi Sarfaraz,

Propellent is a chemical substance which is used to produce energy  or pressurized gas. These are basically energetic materials which are subsequently used to create movement of fluid (liquid / gas) or is generally used for propulsion of objects such as vehicle, projectile etc. Some propellents which are can see in your daily life things are canned whipped cream, hair spray, deodrents etc.

Thankyou!