macOS does not use F5 as a universal refresh key; Cmd+R is the standard.
The "Refresh" action has become a modern superstition. When a Wi-Fi signal is spotty, we hit refresh repeatedly, as if the sheer velocity of our keystrokes will force the data through the airwaves. When a website crashes, we wait ten seconds and tap the keys again, a digital knocking on the door to see if anyone is home yet. keyboard command for refresh