What does it mean if I am not able to taste or smell anything?

Several reasons. It means that your sense of smell (olfaction) is not working, and if absolutely no sense of taste then the gustatory taste areas are not functioning. When you lose smell, you frequently can only taste very minimally, simple things might taste odd to you. This is common with head injury to frontal areas, but could happen with infections, and for taste vitamin deficiencies - see neurologist.