Saving .ods as .xls file through Excel macro

Question

I'm trying to convert multiple .ods files in .xls format. Because of the reasons I can't use Workbook.SaveAs nor Workbook.Open methods, so currently I'm stuck at this:

Public FileName As Variant
Sub Choose()
    Set FileName= Nothing
    ChDrive (ThisWorkbook.Path)
    ChDir (ThisWorkbook.Path)
    FileName = Application.GetOpenFilename _
        (FileFilter:="Excel Worksheets(*.xls; *.xlsx; *.ods), *.xls; *.xlsx; *.ods", _
        Title:="Select a file.", MultiSelect:=False)
End Sub
Sub Saving()
    Call Choose
    ActiveWorkbook.FollowHyperlink Address:=FileName, NewWindow:=True
End Sub

I managed to open a file but, honeslty, do not know what to do next. I do not expect any guidance nor direct answer, but a hint, what should I do and if is it even possible.
P.S. When I open .ods file and save as .xls manualy it work as it should, but I have to think of magic button which will do it automaticaly.