Please use [CODE] tags next time when you include your code in this forum.
You can simply use the in-built excel function "Find" in the code.
This would be as below:
Dim strTodel as String
Dim colTofind as String
Dim delRows as Long
strTodel=InputBox("Enter the String")
Do while True
On Error Goto Err_handle
delRows=delRows + 1
MsgBox "Number of Delete Rows - " & delRows