Can we edit standard print form layouts in user mode? If yes, where?

Yes, in user mode, you can edit standard layouts of print forms. To do this, open the configuration in the 1C system in enterprise mode, go to the "Layouts" or "Print Forms" section (depending on the version and configuration), find the required standard layout, and edit it using the built-in layout editor. Usually, this is done through the "Service" menu → "Edit Layout" or via the context menu of the print form in the document list. Changes are saved and applied when printing documents.