Hide/unhide rows in excel using macro

Try the below code…

Sub HideRowsBasedOnCondtion()
Dim iStart As Integer, iEnd As Long, i As Long, blHide As Variant

iStart = Sheets("First").Index
iEnd = Sheets("Last").Index

blHide = MsgBox("Do You Want To Hide The Rows?", vbYesNo, "Hide Rows?")

If blHide = vbNo Then GoTo UnhideRows

For x = iStart To iEnd
    With Sheets(x)
        For i = 11 To 28
            If .Cells(i, "I").Value = "" Then
                .Rows(i).Hidden = True
            Else
                .Rows(i).Hidden = False
            End If
        Next i
    End With
Next x

MsgBox "Rows Hidden", vbInformation, "Task Completed"
Exit Sub

UnhideRows:
    For x = iStart To iEnd
        Sheets(x).Rows("11:28").Hidden = False
    Next x
    
    MsgBox "Rows Un-Hidden", vbInformation, "Task Completed"

End Sub