Where is the shortcut? If it's on your desktop the usual way is to press and hold until either a menu comes up or you can drag it off the screen (usually to a bin at the top) - precisely how depends on the launcher, and I've never used an LG so don't know their interface.
If you can't remove it (but can remove other icons) that may mean that they have decided it's so important that you don't get a say, like Google do with their search bar and clock widget. In that case the solution is to install a different launcher and use that instead.
If it's somewhere else you'll have to provide more information. Shortcuts in the notification area can usually be edited, but you usually need to pull the slide down all of the way and then either look for an edit button or a context menu (3 dots), again depending on the manufacturer (as they all change the software to some extent).