I suspect that you mean a footer rather than a footnote. Either you have
inadvertently inserted a footer when what you wanted was a footnote, or, if
you do mean a footer but want it just on the first page, you can check the
box for "Different first page" on the Layout tab of the Page Setup dialog
(reached via the dialog launcher in Page Layout | Page Setup), then use the
First Page Footer for your first page footer text.