open a sketch on the front plane and draw a centerline
draw shown sketch..
use mirror command
extrude it. please check the shown places. select offset option and enter 2,30mm. select up to surface option and click on shown surface.
open a sketch on this surface
draw a circle
use cut extrude command and click '' flip side to cut'' box
quickly open a sketch on the front plane and draw a centerline. then exit from sketch