Setting up the guest
Choose to make new Hyper-V guest
Choose a name of the guest
"Generation 1" should be used for RouterOS guests
Select amount of RAM available for the guest, deselect dynamic management
Choose networking capabilities for your new router.
Do not create a new drive for the guest, instead, select option - "Use existing disk" and browse to the download folder where you have downloaded the VHDX image from the MikroTik download page.
Select the downloaded image file.
The summary of the configuration.
Setup is complete, just start the created guest.