When it comes to dual boot, the general idea is that you have a system preinstalled with Windows and then you install Linux alongside Windows. On the boot, you select whether you want to use Windows or Linux.
How about the opposite situation? What if you have a system that has only Linux installed on it and you want to install Windows alongside Linux in dual boot mode?
In this tutorial, I’ll show you exactly how you can install Windows after Ubuntu Linux in dual boot.
Step 1: Create a bootable Windows USB
If you have access to a Windows system, you can follow the instructions on the Microsoft website to create a bootable Windows media.
If you only have a Linux system, creating a bootable Windows USB could be tricky. Thankfully, a handy open source tool called Ventoy helps a lot in this case.
I have written in detailed about creating bootable Windows 10 USB on Linux. Please refer to the guide for detailed instructions. I’ll mention the crucial parts here.
Plug in your USB with at least 8 GB of size and format it. Now, download the ISO of Microsoft Windows.
The above step continues with photos how how to use Linux Ventoy to create a Windows Installation Flash Drive.
Note: from the link mentioned in Step One: https://itsfoss.com/bootable-windows-usb-linux/#second-method