How can I remove android?

My chuwi is Hi12 dual boot. My window storage is almost full. I want to remove android and expand the window storage. How can I do this?
I also have Hi2 keyboard but the backspace key is broken. How can I order just this key?

You can follow this tutorial: You can follow this tutorial: [TUTORIAL] How to remove Android and install Windows on a dualboot tablet (Intel Processors)

The keyboard is not in stock, you could only find it in AlíExpress or in some second-hand sales portal