One thing to be aware of in working through these difficult chapters is that both the original and the current chapter breaks are confusing. The printers must have struggled as they divided this text into chapters. Our modern chapter divisions are very different from the chapter breaks supplied in 1830 and used in the 1837 and 1840 editions as well. That earlier division scheme is very hard to make sense of. For example, Chapter IX in the early printings began where our chapter 19 begins and goes all the way to 3 Nephi 21:21. Chapter X ends at our 23:13. Chapter XI begins with 23:14 and that one chapter contains all of the quotations from Malachi 3–4, ending with 3 Nephi 25:6. And the modern chapters breaks also break up the flow of this lengthy text, which makes it hard to keep in mind the overall flow of what Jesus is saying. So, if you are puzzled about how this text from 3 Nephi 20 to 3 Nephi 26 should be outlined and subdivided, join the crowd!
Moreover, Jesus quoted extensively from Isaiah, Micah, and Malachi in this block of text. Half of the verses in this speech actually come directly from the words that Jehovah (Jesus) had previously spoken to and through these prophets. But the meanings of these words, perhaps intentionally, are in some ways opaque. I have found it at least a little bit helpful to mark these quotations in colored markers and with quote marks, to keep track of which words are coming from Micah, Isaiah, or Malachi.
Identifying these relationships helps make the structure of this Covenant Sermon easier to follow and to see how covenants tie into the principles that the Lord Jesus Christ was teaching here. Above all, don’t get frustrated. This Covenant Sermon actually has an underlying structural order that I think you will find helpful.