Here is what I have found to work for me. I now have all my computers, desktop and two laptops seeing each other and sharing their folders. I do have Windows 10 Pro 20H2 on all three.
First, I went into the Control Panel and set the following. Under uninstall a program I clicked on Turn Windows features on or off. I checked SMB 1.0. See image below for what is selected/checked.Check all your computers on your network to make sure this is selected.
Second, I chose what I want to share by clicking on it then right clicking it and clicking on Properties>Advanced Sharing, checkShare this folder>Set Permissions>OK.
Third, In the image below I clicked onShare under Network Path, chose Everyone as who I wanted to share with, added that, gave read/write permission and clicked on share again.
This image shows that the sharing of my downloads worked.
This image shows my new Laptop with all items shared from my Desktop. Click on, tap or activate image to enlarge it.