How to install original operating system

Within the page they provide you with the operating systems but it is different from what I know, since it is a .rar, and there are no instructions on how to boot it into memory

Make sure you have prepared following before you install the original Windows operating system:

  1. write down your Windows license key, in case the system gets corrupted, using a Windows cmd instruction, so you can re-enter it manually if needed

  2. install on usb using rufus the iso file you downloaded from the microsoft site. Don’t use the chuwi site, as it is not clean like from Microsoft

  3. install on a second usb and unrar the file using 7-zip into a directory the drivers. Go to support.chuwi.com to download the drivers. You will need this to install the drivers after you installed windows, as there will be a lot of missing drivers

  4. prepare a usb mouse, as during the installation and after, the trackpad will not work due to a missing driver

If you don’t understand what I mean, please google for more information.
Good luck!

Check this

Windows installation tutorial: windows installation system tutorial

Driver installation tutorial: Driver installation tutorial