To reduce an image, first create a new Photoshop document by pressing Ctrl + N, or go to File → New. Open the image you want to scroll, then go to the menu above and press Layer → Flatten image. After pressing this command, all layers are intertwined. Even if there are 10 or 20 layers, the merger will each have a single layer, an image. Now you can use the "arrow" moving tool and move the whole picture.
If you see the layer column on the right side of the screen, only one layer appears. Collapse the image to unite all the layers. Just as when you first opened the document because it only has one layer, it will be marked with a background and a small lock icon. Double-click the lock icon to open the icon. Even after the layer is unlocked, the image will be flattering and you will not be able to edit the image or edit the text if you added one.
This does not mean that you can no longer modify it, but only that you first need to fix the image. To cancel scanning, go to Edit → Undo or press Ctrl + Z. This command simply undoes the last action. Previous layers will re-appear as they were before they were merged.
Note that even if the "undo" command is the same, Photoshop does not allow you to perform multiple revocation like Microsoft Word. If you continue to press Ctrl + Z, the operations will not be deleted individually. To do this, Photoshop has another command called Step Backward. So, if you want to undo several steps, press Alt + Ctrl + Z.