Option Explicit
Sub test()
Dim lastRow As Long
Dim ws As Worksheet
Dim i As Long
Dim lastCol As Integer
Application.ScreenUpdating = False
' We have to Loop through all Worksheet Except Output Sheet. Below
'For loop will loop through all the sheets.
For i = 1 To ThisWorkbook.Worksheets.Count
Set ws = ThisWorkbook.Sheets(i) 'This statement will assing the sheet to a variable
If ws.Name <> "Output" Then ' This If will check if the sheet is not Output.
lastRow = ws.Cells(Rows.Count, 1).End(xlUp).Row ' this statement will calculate the last row with data in column A as in the sample data was in column A.
lastCol = Worksheets("Output").Cells(1, Columns.Count).End(xlToLeft).Column ' this statement will check the last column with data in Output Sheet.
If i = 1 Then ' if this is first sheet
ws.Range("A1:A" & lastRow).Copy Worksheets("Output").Cells(1, lastCol) ' than copy and paste data to column A of Output sheet or
Else
ws.Range("A1:A" & lastRow).Copy Worksheets("Output").Cells(1, lastCol + 1) ' copy and paste data to column after the first column.
End If
End If
Next i
Application.ScreenUpdating = True
End Sub