Enter Data into Multiple Worksheets
It's fairly ordinary to need some data to be duplicated in multiple worksheets. You can use Excel's tool for grouping so that data entered in one workbook can be entered into multiple worksheets simultaneously. But therer is also a quicker and more flexible approach that uses a couple of lines of Visual Basic for Applications (VBA) code.
Excel's built-in mechanism for making data go to multiple places at once is a feature called Group. It works by grouping the worksheets together so that they're all linked within the workbook.