Here you go:

You can also copy the following code and paste it directly to your PAD designer. The actions will be created automatically:
Folder.GetFiles Folder: $'''C:\\RPA''' FileFilter: $'''*.xls*''' IncludeSubfolders: False FailOnAccessDenied: True SortBy1: Folder.SortBy.NoSort SortDescending1: False SortBy2: Folder.SortBy.NoSort SortDescending2: False SortBy3: Folder.SortBy.NoSort SortDescending3: False Files=> Files
LOOP FOREACH CurrentItem IN Files
Excel.LaunchExcel.LaunchAndOpenUnderExistingProcess Path: CurrentItem Visible: False ReadOnly: False Instance=> ExcelInstance
# Perform other Excel actions here
Excel.CloseExcel.CloseAndSave Instance: ExcelInstance
END
You will obviously need to change the folder path in Get files in folder. I also applied a filter there to only include Excel files.
The flow will then loop through the files in a For each loop, open the file and close it.
You will need to add some actions for modifying your Excel file where I've put the Comment action. I assume you are able to do those yourself. You have not described the modifications needed anyway.
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