Well, since a Metaphor is basically a figure of speech in which a phrase is applied to an action that isn't literally applicable, an example would be " Love is a Battlefield" or "I am titanium.
for a simile, its a figure of speech comparing one thing to another of a different kind(using like or as), an example would be "She was as busy as a bee" or even "As sweet as sugar"
and for an idiom, it is a word or phrase that isnt taken literally. "its raining cats and dogs" or "break a leg".
