You can drag & drop pages to move them. Drag & drop has two modes - you can temporarily switch between the modes by holding down the ALT key when starting to drag. The default mode is to move pages between each other. The alternative mode - using the ALT key - is to swap two pages.
You drag a page by click-dragging on the drag handle in the upper left corner of the page.
You can drag multiple pages at once, by clicking on the drag handle of each page you want to drag, and then dragging them as a group.
If you need to select multiple adjacent pages at once, you can click on the drag handle of the first page, and then use the SHIFT key and click on the last page you want to drag.