What does the outline pencil do
I push edit in Apple photos,
then the black and white dotted pencil, then what do I do?
iPhone 15 Pro, iOS 17
Question marked as
Are you asking about the outline pencil in the Markup tools?
The pencil that is drawing a dotted line is the lasso button. It is used to select a drawing we have drawn in Markup, so we can move it.
See the paragraph "Draw with Markup" on this help page: Use Markup on your iPhone, iPad, or iPod touch - Apple Support
After you draw something, you can move it around. Tap the Lasso button 
, trace a circle around the drawing that you want to move, then drag it where you want it.