So you know that you can run two Qpps next to each other like on a laptop
Drag and drop the second app next to the open app. It's very easy
You swipe up from the bottom edge, take an app from the bar, hold it briefly and then drag it further up and then to a page and whoosh you have the multitasking view
Swipe up from the bottom of the screen, tap on the app you want to run sideways, hold it down and drag it to the right or left. The picture will then split automatically. As soon as you let go, the desired app fits into the desired page.