How to declare specific range on worksheet on workbook

Hi there,

I have written this script to update a spreadsheet from another spreadsheet, but I think the code is a little messy and could be tidied up if I was able to use the variables the way I indended.

Sub Upload()
    Application.ScreenUpdating = False
    Workbooks.Open Filename:= _
            "C:\Documents\DestinationSheet.xlsx"
    
    Dim rSource As Range
    Dim rDestination As Range
    
    Windows("Timesheet.xlsm").Activate
    Sheets("Monthly_Totals").Activate
    Set rSource = Range("B11:N18")
    rSource.Select
    rSource.Copy
    
    Windows("DestinationSheet.xlsx").Activate
    Sheets("P15").Activate
    Set rDestination = Range("B31")
    rDestination.Select
    
    rDestination.PasteSpecial Paste:=xlPasteValues, _
    Operation:=xlNone, _
    SkipBlanks:=False, _
    Transpose:=False
    
    Windows("DestinationSheet.xlsx").Activate
    ActiveWindow.Close
    
    Application.ScreenUpdating = True
    ActiveWindow.WindowState = xlMaximized
    Worksheets(1).Activate
    Range("A1").Select
    Application.CutCopyMode = False

valKill:
    Set rSource = Nothing
    Set rDestination = Nothing

Exit Sub
End Sub

Basically, I would ideally like to use the variable of rSource and rDestination to refer to the specific ranges on a specific sheet on another workbook. Is there a better way to do this please.

Kind regards

Rob