Meaning: This sentence is saying that imagination is the driving force behind creativity.
Choice of Words: Imagination is the ability to think about things that are not real. Fuels means to provide something with the energy or resources that it needs to operate. Fire is a hot, burning mass of flames. Creation means the act of making something new. When you put them together, "Imagination fuels the fire of creation" means that imagination provides the energy and inspiration needed to create something new.