How to stop Win 10 accessing Internet but allow local access?

[LateJUnction]

When Win 10 support ends I plan to continue to use it, but I want to prevent Win 10 from accessing – or being accessed by – the internet, while allowing free access to my home network. I’m sure this is readily achievable; could somebody point me to a well respected how-to document designed to be used by non-networking non-experts?

 

[Grizzly]

I do not have a source available but you should be able to block internet access for that computer in your router.
I have a couple of devices that I do not want to access the WWW and I blocked them in a setting of my router. They still are able to access my local network though.
Might give you an idea.....

 

[ClippyBeer]

The easiest way would be to set a static IP address and set default gateway to 0.0.0.0