If you want to rearrange folders or items within a course content page, you should be able to do this simply by dragging the item to the desired position – see How to rearrange content items on a page.
However, if you have a large number of items on the page, you may find that this is impossible to do. In which case you can use “keyboard accessible reordering” to place items in the desired position – here’s how to do it.