Questions about example sentences with, and the definition and usage of "Okinawan"

A: The "what" serves the purpose of bridging the comparison between Okinawan food and the kind of food the speaker normally eats. It lets the other person know that they're making a direct comparison between the two types of food.

Without it, the sentence becomes grammatically incorrect and sounds very awkward.

A: On the way from (Place A) to (Place B), I stopped in the Okinawan traditional house cafè for lunch.

A: Okay, I'll do the corrections.
Use “a” before words that start with a consonant sound and “an” before words that start with a vowel sound. Other letters can also be pronounced either way. Just remember it is the sound that governs whether you use “a” or “an,” not the actual first letter of the word.

So from 'a okinawan old man' change it to...
An Okinawan old man joked.

Also, the joke is in past tense so it should be joke with a -ed but since joke already has an 'e' just add -d.

He said, "I will go to Hawaii"

"Go to Hawaii" means " to go to the afterlife".
although means and mean is almost mean the same thing but in this sentence it is more appropriate to use 'means'.

A: I can speak very little Okinawan dialects.

I can speak a little in Okinawan dialect.