You can drop multiple files in at once, or one by one. To change the order in which individual files will appear in the final, merged document, click and drag the file up or down the list.

To combine PDF files into a single PDF document is easier than it looks. Read on to find out just how to combine multiple PDF files on macOS and Windows 10.

You can drag and drop files into OneDrive by locating and selecting them in Windows' File Explorer and moving them to the OneDrive folder.