by default, when you apply bullet behavior it moves object left to right -----> at the speed specified
I want ability to start with bullet going right to left <------- or up and down.
so that natural angle of sprite and default bullet direction match
The "natural angle" is 0 degrees, so it's probably best to design all of your objects facing 0 degrees. (All of your objects that can turn around and move in different directions, that is.)
If you want the object to face a different direction when the game starts running, use the "Set angle" action in a "Start of layout" event.