It doesn’t even run on 3.3 V! Use a Li-Po battery or a DC-DC buck converter instead.
Keep in mind that the SIM800L chip has an operating voltage range of 3.4 V to 4.4 V, so connecting this module to the Arduino’s 5V output is probably going to cause damage to the module. NET pin is where you can solder the helical antenna that comes with the module.
