Usage Issue

I am trying to install a “3D Touch” bed leveling sensor on a Geeetech A20M 3D Printer. When trying to adjust the firmware using Marlin and ArduinoIDE (version 1.8.9, in configuration.h) when I try to “verify or upload” the adjustments, I receive the error message ” U8glib.h: No such file or directory exit status 1”. What am I doing wrong and how do I fix this? Your advice would be greatly appreciated.

The code you are trying to compile uses the U8glib library.

You have not installed said library, or have installed it incorrectly.