Some questions about external monitors.

I've bought an adaptor to connect my Pixelbook to my monitor as I plan on not taking my desktop home from uni over Easter and just taking my laptop, keyboard, mouse and monitor.

It's all working great but I'd like to ask couple of questions about setting it up for certain things.

1. As I have a keyboard and mouse I would like for my Pixelbook to be in tent or reversed mode rather than traditional laptop mode. This seems to make the shelf on the Pixelbook go away and forces it to the bottom on the monitor. I'd like to have them on the extremes on either side of my total display space if this is possible as it is when in normal laptop mode. (So the shelf on the left of the Pixelbook and right of the monitor)

2. Now that I'm typing this out it is pretty much the same thing actually. I'd like to be able to write on my Pixelbook in tablet portrait mode while still using my monitor. When I try this however the shelf is once again forced to the bottom of the monitor and disappears from the Pixelbook.

Any help would be appreciated, thank you.