Quickest way to launch camera app on Samsung Galaxy Note 9

Camera is the mostly used app on smart phones, and its frequently required app. Having quick shortcut to launch the camera is always helpful. 
Samsung Galaxy Note 9 offers the always on display mode, where it allows to enable on screen home button.  Always on display also allows to set camera as a app to launch when double tap on home button. 

To enable this go to Setting -> Lock Screen -> Always on Display. On always on display settings choose action for "Double tap Home Button". To use this shortcut you should also select "Home button and clock" under Contents to shown on the same screen.