To add additional languages for your keyboard

From the Home screen, touch and hold the Recent Apps Key (in the Touch Keys bar) > Settings > Language & input. Tap the Settings icon to the right of LG Keyboard, tap Input language and keyboard layout, then checkmark the languages you want the keyboard to be able to use.

OR

Open the Notifications panel (when an app that allows text input is open), tap Choose input method (in the ongoing notifications list) > Setup input methods (at the bottom of the dialog box) > the Settings icon (to the right of LG Keyboard) > Input language and keyboard layout, then checkmark the languages you want to be able to use.