Jose_Roberto_Chaurais​ SMB 1.0 can still be installed in Windows 11 25H2 via "Turn Windows features on or off" or PowerShell. It is still available in Windows Insiders, as well. See posts and comments for details about how to install and enable it.
To see other computers from the Network node in File Explorer you should first make sure the network connection profile is set to Private, and not Public. You can check this in PowerShell with this command.
Get-NetConnectionProfile
To change from Public to Private run this command.
Get-NetConnectionProfile | Set-NetConnectionProfile -NetworkCategory Private
Next, make sure network discovery is enabled by going to Settings > Network & Internet > Advanced network settings > Advanced sharing settings. Expand "Private networks" and toggle on "Network discovery". Optionally, if you are sharing file on the device (you have a share that other workgroup systems access), you can also toggle on "File and printer sharing".
You will need mDNS enabled (default) for network discovery to work with Windows 11. You may need UPnP, NetBIOS, or LLMNR enabled to see older versions of Windows or legacy/non-Windows devices.