I know about the money, pay me 43613 or I tell the world.
A: What does this mean, “I know about the money?”
B: What it means DON’T matter. It’s blackmail. I didn’t bring you here for what it means. I brought you here make it stop.
I’d like to know the sentence is grammatically correct? Or it’s just the way some people say?
A. Presumably there is some money involved in this story and the speaker it stating that he or she knows about it.
B. “What it means DON’T matter.” I would say this is not really correct but it is something you might hear a lot in informal speech. More formal, and probably more correct, is “what it means doesn’t matter” or equivalently “what it means does not matter”.
“It doesn’t matter” is grammatically correct.
“It don’t matter” is not grammatical. It will be encountered in some informal slangy speech. You want to recognize it, but you as a learner do not want to speak this way.
As already pointed out: “What it means DON’T matter.” is grammatically wrong, but there are some people who talk like that. It could be something an Italian gangster in a movie would say.
The correct way to use the verb is: I do. You do. He does. She does. It does. They do. It doesn´t matter. They don´t matter etc.
In the past tense it´s always “did”.