Geomorphology is the study of why the landscape is shaped how it is. Why is there a mountain there, and how did it come to be? Ask someone who knows about geomorphology.
Morphology is a word that means "the study of shape." It's used in linguistics (the shapes of words), biology (the shapes of animals) and geology (the shapes of landscapes). When it's used in a geology context, it's sometimes called geomorphology just to let you know which type of morphology you're dealing with. Geo means "land" or "earth," so you could think of geomorphology as meaning "the study of the shape of the land."