You can open two instances of Notes Writer on your iPad, side by side, with iOS 13 new "Split View" feature.
How to use Split View:
- Open Notes Writer.
- Swipe up from the bottom of the screen to open the Dock.
- On the Dock, touch and hold the second app (in this case, Notes Writer) that you want to open, then drag it off the dock to the left or right edge of the screen.
How to adjust Split View:
- To give the apps equal space on the screen, drag the app divider to the center of the screen.
- To turn a Split View into a Slide Over, swipe down from the top of the app.
- To close Split View, drag the app divider over the app that you want to close.
You can find videos and more details here: