What purpose does the mass airflow sensor/meter served... also,could it in anyway prevent the car engine from turning over?

The Mass Airflow Sensor (MAF) provides a vital input to the Engine Control Module (ECM).
It's purpose is to calculate, very accurately, the amount of air moving into the engine. The ECM uses that information and information from other sensors to adjust fuel volume to provide the proper mixture.

While the MAF is necessary for the engine to run properly, it won't prevent the engine from turning over.