You can try something like this - it's not tested, and can be made more elegant, but this seemed the simplest to start with
Option Explicit
Sub test()
Dim iFile As Long, j As Long
Dim bStart As Boolean
Dim textline As String
Dim newline As Variant
iFile = FreeFile
bStart = False
Do While Not EOF(iFile)
j = j + 1
Line Input #1, textline
If textline = "Start line" Then
bStart = True
GoTo Nextline
ElseIf textline = "This is the stop text" Then
Exit Do
ElseIf bStart Then
newline = Split(textline, ",")
Cells(j, 1) = newline(0)
Cells(j, 2) = newline(1)
Cells(j, 3) = newline(2)
Cells(j, 4) = newline(3)
End If
Nextline:
Loop
Close #iFile
End Sub