"Kaʻiulani loves ʻawa."
Translation:Puni ʻo Kaʻiulani i ka ʻawa.
It is also the name of the plant which produces the drink. The version we use in English "Kava" comes from Tongan which is a closely related language that often uses k where Hawaiian uses ' and writes v where Hawaiian writes w. So Tongan kava is the exact same word as Hawaiian 'awa. It is a little confusing that the English sentence uses the Hawaiian spelling even though many English speakers use the Tongan word, but I imagine that in Hawai'i the Hawaiian word is often used even in English. In a search engine, you are more likely to find helpful results with the spelling "kava".
In this instance, "puni" is acting as the verb and in Hawaiian the verb comes first. Then following the verb should be the grammatical subject - the one doing the action of the verb. Who is doing the "loving" in this case? Ka‘iulani. So we have, "Puni ‘o Ka‘iulani". Then, finally, you add the grammatical object - the thing the action is done to. What is it that Ka‘iulani loves? Kava. So we get the final sentence above.
That is not really a verb-subject-object sentence, so it's a little different. There the 'O is used to mark that it's an equivalence (copular) sentence which doesn't include an indefinite and it is used to start the sentence regardless of whether the first element of the equation is a general noun, a proper noun, or even a pronoun. When you see a sentence start with that, you know that there are going to be two noun phrases and that the sentence is saying that those two things basically describe the same thing. So in your example, "what thing = your desire?"