If you use Flatpak apps on Linux, do yourself a favor and install Bazaar to make your app management life a bit easier.
You can see if you're running the latest macOS version by clicking the Apple logo in the top-left corner, then selecting ...
Install nmap if you don't already have it on your Linux computer. Run "sudo apt-get install nmap" on Ubuntu, or "sudo dnf install nmap" on Fedora. To investigate devices, try looking up OUIs, scanning ...