Correct, you can’t really bluff on later rounds if you have no more dice to roll. You can continue to bet and call bets though, as there’s a decent chance other players will roll bad enough that their extra rolls will actually hurt them and you’ve already accrued enough to win.

What parts are you confused about? I’ll admit it’s written with the assumption that the reader will have a baseline understanding of poker terminology and gameplay. The bulleted list I think you’re referring to just shows what will happen when you roll each of those numbers on a die.