Esc's need a sequence to arm ( turn on motor control) themselves so to not accidentally take a finger by a spinning prop.
Then some esc's can be programmed by certain stick (pulse width) positions.
For normal operation (not programming) on some esc's the the throttle is set at full on before hooking up the battery then after the (2?) beeps the throttle is set to the neutral position.
I have never done it but it maybe possible to see what the actual pulse rate is by using the pulseIn command and monitoring what the esc is seeing. A common ground between the receiver and arduino and a way to "splice" into the signal.