Blueprint function library (get hdd serial), (DWORD GetHDDSerial) function

Hello guys!
I need to make a blueprint node which gets my HDD serial number and after that it returns it to an FString.
Tried many times and had many errors after building.
I’am newbie in c ++, just starting to explore this amazing side but can’t get through.
Could you help and show me the code for the .h and .cpp files.
Many thanks!

this function
DWORD GetHDDSerial()
{
DWORD serialNumber;
GetVolumeInformation("%SystemDrive%",0,0,&serialNumber,0,0,0,0);
return serialNumber;
}