To duplicate a record (row), simply right-click on a record and select the Duplicate record option from the dropdown menu.

For another way to duplicate a record, you can also hold down the Alt key while picking up a record from the drag handle on the leftmost side of the record. While you're dragging the record and holding down Alt, a green plus sign should appear. When you drop the record, a copy of the record you dragged will be created at the place where you dropped it.