Just like Multi-Editing Feature we have Column Mode Editing in Notepad++. We can select multiple lines for editing by Holding Alt key + Mouse Drag.
This might be helpful in various scenarios, say if you want to add something at the start of each lines and at the end of each line or to make a Sql Script form a CSV file.
This may not be useful if you want to edit certain text at certain parts of the document for this you may have to try Multi-Editing. Check out the tutorial on How to use Multi-Editing with Notepad++ : link