Wire.h missing - Failing to upload I2C 16x2 LCD sketch
That library is special. It expects to be placed in the same location as the Wire library.  You need to find the location of the Wire library and place this library alongside it.  So you have:

.../Wire/Wire.cpp
.../Wire/Wire.h
.../LiquidCrystal_I2C/LiquidCrystal_I2C.cpp
.../LiquidCrystal_I2C/LiquidCrystal_I2C.h


etc