Where has this been all my life!?
"said" is an invisible word. people don’t notice it. they notice quotes and the nouns that address who is saying it.
my personal rule is to use a word other than “said” if you otherwise can’t tell the emotion that is being portrayed in speech. overuse of alternatives just makes you look like you’re trying too hard.
writing is about style but, like art, you have to know some basics before delving into your novel.