: Before starting the installation, ensure you have backed up all your important data. Installation of an operating system can potentially erase data on the partition you are installing on.
If you must run a specific legacy application that only works on Windows 7, install an official, unmodified Windows 7 ISO inside a virtual machine (like VirtualBox) and disconnect its virtual network adapter from the internet. : Before starting the installation, ensure you have
What will the computer be (web browsing, gaming, office work)? : Before starting the installation