You can install Windows 10 without a key (click "I don't have a product key") – it will run indefinitely with a watermark and limited personalization.
The tool itself can create the USB directly without needing Rufus. Just run the tool, select "USB flash drive," and follow prompts. microsoft windows 10 home pro x64 clean iso
Microsoft releases major updates twice a year (22H2, 23H2, etc.). Your ISO will become outdated. To stay current: You can install Windows 10 without a key