In my mind, "crank" as it relates to a car, is what happens when you turn the key to the start position - the starter motor engages and cranks the engine - under normal circumstances, the engine starts, you release the key, the starter disengages (stops cranking the engine), and the engine continues to run.
The cranking "phase" would normally last for maybe 5 to 10 seconds.
If your engine is not starting then there are a number of things that need to be checked - you can start by ensuring there is fuel in the tank.
It will start up but will not continue running; engine stops after ??? seconds.
Is this a petrol engine or a diesel ? Fil up your profile/signature with ALL..ALL details about car, year, model, engine type, mileage, transmission type..... so relevant replies can be forwarded.