Will the following help by inserting a PageBreak Cell as one would manual with insert menu:

nb = CreateDocument[];
    NotebookWrite[nb, Cell["A Heading", "Section"]];
 NotebookWrite[nb, 
     Cell["", "PageBreak", PageBreakBelow -> True]];
    NotebookWrite[nb, Cell["New content", "Subsection"]];
    NotebookWrite[nb, 
      Cell[BoxData[
        TagBox[GridBox[{{"\<\"Column 1\"\>", "\<\"Column 2\"\>"}, {"True",
             "False"}}, AutoDelete -> False, 
          GridBoxBackground -> {"Columns" -> {{None}}, 
            "Rows" -> {RGBColor[0.88, 1, 0.88], RGBColor[1, 0.85, 0.85]}},
           GridBoxFrame -> {"Columns" -> {{True}}, "Rows" -> {{True}}}, 
          GridBoxItemSize -> {"Columns" -> {{Automatic}}, 
            "Rows" -> {{Automatic}}}], "Grid"]], "Output", 
       ImageSize -> {224, 38}, ImageMargins -> {{0, 0}, {0, 0}}, 
       ImageRegion -> {{0, 1}, {0, 1}}, CellLabel -> ""]];
    NotebookWrite[nb, Cell["", "PageBreak", PageBreakBelow -> True]];
    NotebookWrite[nb, Cell["New content", "Subsection"]];
    NotebookWrite[nb, 
      Cell[BoxData[
        TagBox[GridBox[{{"\<\"Column 1\"\>", "\<\"Column 2\"\>"}, {"True",
             "False"}}, AutoDelete -> False, 
          GridBoxBackground -> {"Columns" -> {{None}}, 
            "Rows" -> {RGBColor[0.88, 1, 0.88], RGBColor[1, 0.85, 0.85]}},
           GridBoxFrame -> {"Columns" -> {{True}}, "Rows" -> {{True}}}, 
          GridBoxItemSize -> {"Columns" -> {{Automatic}}, 
            "Rows" -> {{Automatic}}}], "Grid"]], "Output", 
       ImageSize -> {224, 38}, ImageMargins -> {{0, 0}, {0, 0}}, 
       ImageRegion -> {{0, 1}, {0, 1}}, CellLabel -> ""]];

Hello Vitally,

Thank you for responding. The examples for PageBreakBelow and PageBreakAbove appear to set the page breaks for all cells of a given type for an entire newly-created notebook. I just want to set breaks for two particular cells.