Sub MergeMultiSheets()
Dim wbDst As Workbook
Dim wbSrc As Workbook
Dim wsSrc As Worksheet
Dim MyPath As String
Dim strFilename As String
    
    Application.DisplayAlerts = False
    Application.EnableEvents = False
    Application.ScreenUpdating = False
    MyPath = "D:\MyPath" ' change to suit
    Set wbDst = Workbooks.Add(xlWBATWorksheet)
    strFilename = Dir(MyPath & "\*.xls", vbNormal)
    
    If Len(strFilename) = 0 Then Exit Sub
    
    Do Until strFilename = ""

            Set wbSrc = Workbooks.Open(Filename:=MyPath & "\" & strFilename)
            
            Set wsSrc = wbSrc.Worksheets(1)
            
            wsSrc.Copy After:=wbDst.Worksheets(wbDst.Worksheets.Count)

            wbSrc.Close False
        
        strFilename = Dir()
        
    Loop
    wbDst.Worksheets(1).Delete
    
    Application.DisplayAlerts = True
    Application.EnableEvents = True
    Application.ScreenUpdating = True
End Sub