Open the Pages panel
Select the page or pages you want to move
Drag the selected pages to the desired location within the same document
Release the mouse when the insertion indicator appears in the correct spot
To move multiple pages, Shift-click or Ctrl-click / Cmd-click to select them first
To move a spread, drag the entire spread in the Pages panel
If needed, use the Page Tool to reposition pages on the canvas
Save the document after moving the pages