|I already gave you the "Easy formula". =Sheet1!A1, =Sheet1!A2, etc.|
However, if you don't want to pre-populate Sheet2 with a bunch of =Sheet1 formulas, you'll need to use a macro.
Right click the sheet tab for Sheet1 and choose View Code.
Paste this code into the window that opens:
Private Sub Worksheet_Change(ByVal Target As Range)
Sheet2.Cells(Target.Row, Target.Column) = Target
Everything you enter into any cell in Sheet1 will be copied to the same cell in Sheet2.
However, once again, I'm sure that there is more to this than you are telling us. I see no point in having an exact duplicate of a given worksheet in the same workbook.
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