The haptic feedback and keypress sound are both enabled on the LG 5 by default. To disable and turn keyboard sound and vibration on LG G5, upon typing, do as follows:
1. Open the Settings app on your G5 (Simply drag down the notification bar, and touch the Gear icon on the top)
2. Scroll down to the Personal settings, and then tap to open the Language & Keyboard option (On the tab view, go to the General tab)
3. Under the list of available keyboards, find the LG Keyboard and tap the Gear icon next to it to open the keyboard's settings
4. Scroll down to More and tap to open it
5. Now, under the Effects settings, make sure to unchecked both Vibrate on Keypress and Sound on Keypress options.