Photography: Playing with Flash

I’m still working my way through my photography class and the most recent less is about flash.  There are two types of flash – internal and external.  Internal is the kind that is connected to your camera and you cannot remove.  External is an extra accessory that you attach to your camera.   I generally let my camera decide whether or not it wants to use a flash.  That’s generally not what *professional* photographers do because they prefer to control the lighting themselves.   These are two photos I took today of a lily. The first is with no flash. The second is with flash. I’m not sure either is ideal as far as lighting?