Auto-Insert Rows when Data is entered & then merge cells - vba

Question

When data is entered (user has hit "return") into any cell in Column B, I want to insert four rows directly below the row that just had data entered into it.
I want the program to run automatically after the user has hit return on the cell. I've been having three sticking points:
Finding a way for the program to run without the user having to hit a button. I've spent a fair amount of time searching for example code to use and have found several resources, but the two examples I've used haven't seemed to work. PDCA is the sheet name, Add_Row is the macro I've written to add rows below the user-inputted data.
Private Sub Worksheet_Change(ByVal Target As Range)
If Not Intersect(Target, [B3:B14]) Is Nothing Then Sheets("PDCA Tracking").Add_Row
End Sub
Actually running the Add_Row program. I get an Error 1004 Application Defined or User Defined Error. My second question is, when the user hits return, the active cell wouldn't be the one s/he just entered data in then, would it? How would I mitigate that? It would be the last row of the spreadsheet, could I find the last row and then just add rows below that?:
Sub Add_Row'Insert row below active cell
ActiveCell.Offset(1).EntireRow.Insert
Cells(ActiveCell.Offset(1), 3).Value = "Zulu"
ActiveCell.Offset(2).EntireRow.Insert
Cells(ActiveCell.Offset(2), 3).Value = "Yankee"
ActiveCell.Offset(3).EntireRow.Insert
Cells(ActiveCell.Offset(3), 3).Value = "X-Ray"
ActiveCell.Offset(4).EntireRow.Insert
Cells(ActiveCell.Offset(4), 3).Value = "Whiskey"
'Call Merge_Cells
End Sub
After I enter the data, I want to take the cells below the row where the user just added the data and merge them. (ie if the user input "banana" and I added four rows below "banana", I want JUST the four new cells under banana to merge with the cell containing "banana". I know there's a .Merge command but again, not sure of the syntax to use.
Any and all help is very appreciated!
UPDATE: I figured out how to add data below the last filled in row, I believe.
Dim lastRow As Long
lastRow = Range("A" & Rows.Count).End(xlUp).Row
Cells(lastRow + 1, 3).Value = "Zulu"
Cells(lastRow + 2, 3).Value = "Yankee"

Answer 1

Private Sub Worksheet_Change(ByVal Target As Range)
On Error GoTo haveError
If Target.Cells.Count = 1 And _
Not Application.Intersect(Target, [B3:B14]) Is Nothing Then
Application.EnableEvents = False
With Target
.Offset(1, 0).Resize(4, 1).Insert Shift:=xlDown
.Resize(5, 1).Merge
.VerticalAlignment = xlTop
End With
Application.EnableEvents = True
End If
Exit Sub
haveError:
Application.EnableEvents = True
End Sub