If you had a face like mine, you’d punch me right on the nose, and I’m just the fella to do it.

Meaning of the quote

The quote suggests that the speaker believes his own face is so unpleasant that if someone else had a face like his, they would want to punch him in the nose. He also says he's the kind of person who would do that to himself, if he had his own face. In other words, the speaker is making a joke about how unattractive he thinks his own appearance is.