Hi gspandi0503 welcome to the forum,
Perhaps the below will get you started:
Sub Test()
Dim sFile As String, tWb As Workbook, tWs As Worksheet
Dim sWb As Workbook, sWs As Worksheet
Set tWb = ThisWorkbook
Set tWs = tWb.Sheets("StartData")
With Application.FileDialog(msoFileDialogFilePicker)
If .Show = -1 Then
sFile = .SelectedItems(1)
End If
End With
If sFile <> "" Then
Set sWb = Workbooks.Open(sFile)
DoEvents
Set sWs = sWb.Sheets("EndData")
tWs.Range("B5:BP250").Value = sWs.Range("B5:BP250").Value
sWb.Close False
End If
End Sub