Sets or returns an int that represents the number that the page numbering starts at for this section.

public int FirstPageNum{ get; set; }
Public Property FirstPageNum() As Integer

MS Word equivalent: Insert menu > Page Numbers... > Format... button > Start at:

          //--- Return FirstPageNum
          int firstPageNum = oSection.FirstPageNum;

          //--- Set FirstPageNum
          oSection.FirstPageNum = 2;
        
          '--- Return FirstPageNum
          Dim firstPageNum As Integer = oSection.FirstPageNum

          '--- Set FirstPageNum
          oSection.FirstPageNum = 2