Rotate screen on HyperV

First you need to make sure you install and configure Hyper-V accurately.
1. How to install Hyper-V?
2. How to configure Hyper-V?

After checking that you need to follow these steps.
3.I also encountered this issue here what i did on 1366 x 768 display. This made it hard to use Hyper-V virtual machines, Hyper-V default is 1024 x 768 and its only allow you to configure 4 x 3 resolutions.

Luckily, it is actually possible to setup a Hyper-V virtual machine with a widescreen resolution. Though the process is not that intuitive. What you need to do is:

Right click on the desktop of the virtual machine and select Screen Resolution
Select Advanced Settings
Click List All Modes
Choose the screen resolution that you want and click OK.
You can also use this method to set the virtual machine resolution to 800 x 600 or 640 x 480 – which is usually not allowed on recent versions of Windows.