How do I find out which operating system I use with the laptop?

How do I find out which operating system I use with the laptop?

https://www.wieistmeineip.de/

shows you next to your IP and your operating system and the browser you use.

With me quite "PC Infos" in the search bar to find something suitable. Usually you can also see it on the desktop itself

Start laptop.

Normally, it indicates which operating system is started.

You look. It can't be so hard to distinguish a Windows from a MacOS or a Linux. If the operating system was already preinstalled, it was probably Windows anyway.

If you dive your notebook underwater and repeat "Our Father" three times in a row, the operating system version will be revealed to you.

But only if you do not change the referer ;-)

If you do that, you usually know what the operating system is.