This is the lyrics of Spongebob theme song in Chinese translation. The original English text was thrown on the deck, flapping like a fish. I fell on the deck and rolled like a fish. This sentence itself has no clear meaning, mainly a cheerful atmosphere. The first sentence of the theme song is if childish nonsense is what you want, which literally translates as "if nonsense is your deep-sea dish", so the next sentence has no specific meaning.