How to use insertNewUnstyledBlock()?

[kurisLei]

As shown in the figure, when I use the insertNewUnstyledBlock() in a block with content, I hope to jump out of this block and create a new unstyle block. The fact is that he did create a new block, but in the original block he seems to be executed. Like split-block, And I need to wrap it twice. can you guide me how to deal with this problem?