Open multiple excel files on sharepoint using VBA

Hi,
I'm new to this forum and hope for some help. Thanks in advance to the cool experts.

I would like to open a file dialog where the user can select multiple Excel files which then will be opened and values extracted into a consolidation Excel workbook. Have tried to change my code in a fileserver environment to a SharePoint equivvalent - but it doesn't work.

Sub TestSharepointFileOpen()
    'Declare a variable as a FileDialog object.
    Dim fd As FileDialog
    'Declare a variable to contain the path of each selected item. Even though the path is aString,
    'the variable must be a Variant because For Each...Next routines only work with Variants and Objects.
    Dim vrtSelectedItem As Variant
    Dim wbBusinessCase As Workbook


    Application.ScreenUpdating = False
    Application.DisplayAlerts = False
    Application.EnableEvents = False 


    'Create a FileDialog object as a File Picker dialog box.
    Set fd = Application.FileDialog(msoFileDialogFilePicker)
    fd.InitialFileName = "\\sites\projects\"

    'Use a With...End With block to reference the FileDialog object.
    With fd

        'Allow the user to select multiple files.
        .AllowMultiSelect = True

        'Use the Show method to display the File Picker dialog box and return the user's action.
        'If the user presses the button...
        If .Show = -1 Then
            'Step through each string in the FileDialogSelectedItems collection.
            For Each vrtSelectedItem In .SelectedItems
                Set wbBusinessCase = Workbooks.Open(vrtSelectedItem, ReadOnly:=True) 'actual command to open each file
                wbBusinessCase.Close SaveChanges:=False 'close each file after it has been copied from
            Next
        'If the user presses Cancel...
        Else
        End If
    End With

  
    Application.ScreenUpdating = True
    Application.DisplayAlerts = True
    Application.EnableEvents = True 

End Sub