I happen to have a macro that pretty much does this, so I just tweaked it to match your data. Otherwise, I'd also ask that you show some effort first. I assume your data is in column A ("testa", "second", etc) and column B (the delimited data)
Sub splitCopyDown()
Dim rng As Range, cel As Range
Dim cols As Long, lastRow As Long, i As Long, k As Long
Set rng = Range("B1:B" & Cells(Rows.Count, 2).End(xlUp).Row)
rng.TextToColumns Destination:=Range("B1"), Semicolon:=True
lastRow = Cells(Rows.Count, 2).End(xlUp).Row
For i = lastRow To 1 Step -1
cols = Cells(i, Columns.Count).End(xlToLeft).Column
Set rng = Range(Cells(i, 3), Cells(i, cols))
Range(rng.Offset(1, 0), rng.Offset(cols - 2, 0)).EntireRow.Insert
rng.Copy
rng.Cells(1).Offset(1, -1).PasteSpecial Paste:=xlPasteAll, Operation:=xlNone, SkipBlanks:=False, Transpose:=True
rng.Clear
Next i
lastRow = Cells(Rows.Count, 2).End(xlUp).Row
Range(Cells(1, 1), Cells(lastRow, 1)).SpecialCells(xlCellTypeBlanks).FormulaR1C1 = "=r[-1]c"
Range(Cells(1, 1), Cells(lastRow, 1)).Value = Range(Cells(1, 1), Cells(lastRow, 1)).Value
End Sub
(It's an older macro, but it checks out. You could likely make it more efficient)