How do I work on two documents at the same time?

I’m in Writer and I would like to open two text documents to work on.

Have you tried opening the first document and moving the window to one side of the big screen (you need a big screen) and then opening the second document and moving it more to the other side of your big screen. Assuming the windows don’t overlap completely, you can click on whichever document you want to have on top at the time and go back and forth between them easily. The key is to have a larger than average screen, and to size each window so that it is not “full screen” but is still large enough to accommodate enough of the document to work on. I do this all the time.