Connecting to a Windows machine from a separate, Ubuntu machine on my home network

I have Windows 10 on one machine and Ubuntu 20.04 on another, completely separate machine. They both connect to the internet through my home network. My Windows machine has no problem at all seeing the Ubuntu machine and can access that machine through shared folders. This is all great; but I would like it to work the other way too.

When I open the Files utility on the Activities bar and then click on Other Locations I can see a pretty purple icon which is labelled Windows Network. When I click on that, all I see is an empty folder.

If I ping the Windows machine from the terminal all I get is Destination Host Unreachable.

Does anybody know what I might be doing wrong?

Update: I don't know how to configure the windows firewall, but I did turn it off in Windows Defender. I also checked the IP addresses and those are also ok.