The words <em>goal </em>and <em>mole </em>have several similarities, but also several differences. When it comes to the similarities, these two words rhyme - they only differ in their initial letter (g and m), but apart from that, they sound pretty much the same. Other than that, both words are nouns - they belong to the same group of words.
When it comes to their differences, the obvious one is that they have completely unrelated meanings. Even though they sound similar, their meanings are nothing alike.