Option Explicit
Sub test()
Dim LastRow As Long, i, j As Integer, Val As String
With Sheets("Sheet1")
LastRow = .Cells(.Rows.Count, "A").End(xlUp).Row
j = 2
For i = 1 To LastRow
Val = .Cells(i, 1)
.Cells(1, j) = Left(Val, Application.Find(":", Val, 1))
.Cells(2, j) = Right(Val, Len(Val) - Application.Find(":", Val, 1))
j = j + 1
Next i
.Columns("A:A").Delete
End With
End Sub