Hello Danny,
Thank you for your demand.
Yes, you can double click on a Windows ISO while Windows is running and thus make it available as a separate drive.
If you then start the setup.exe, you can also carry out the upgrade.
This procedure is also known as an in-place upgrade.
You don't necessarily have to create a USB stick or DVD with the ISO.
Greetings
Thanks Tekkie, I'll give that a go!
Just a quick note on vocabulary - you might want to use a more sophisticated translator. 'Thank you for your demand', is a phrasing so intrinsically self-contradicting that it carries passive-aggressive implications which I'm sure you didn't mean. My 'request' for help was a friendly and unassuming message asking for advice without any expectation from anyone other than a friendly hope that someone might spare their time and expertise (which you very kindly did). A 'demand' is a good way to describe a prison guard telling an inmate to cut off his own fingers.