To duplicate, copy & cut, select objects using lasso tool, tap the three-dot menu button.

If you tap Duplicate, the selected objects will be immediately duplicated near the already selected objects.

If you tap Copy, the selected objects will be added to clipboard, which can be found inside the library tool. Tap or drag items from clipboard to paste. Clipboard keeps your most recent 10 copy/cut items.

If you tap Cut, the already selected objects will be deleted and a copy of it will be added to clipboard.

If you tap Add to library, the already selected objects will be added into the library tool, which can be reused across pages and notes. Unlike clipboard, items inside library are stored persistently.