How to make all other programs muted in windows?

Yes, when the user presses: "Start relaxing music for sleeping" he would be warned and the program would explain that all other processes would be muted so no notification wakes him up for example...

Thanks, it linked then to here:

https://stackoverflow.com/questions/20938934/controlling-applications-volume-by-process-id

And in the main answer there's a code to include in my app with this in it to make it work:

// dump all audio sessions
foreach (AudioSession session in AudioUtilities.GetAllSessions())
{
if (session.Process != null)
{
// only the one associated with a defined process
Console.WriteLine(session.Process.ProcessName);
}
}

How do I make here please something like:
if(Session.Process!=thisProcess) {/*mute process*/}

Is it this one:

https://docs.microsoft.com/en-us/dotnet/api/system.diagnostics.process.getcurrentprocess?view=net-6.0

?

EDIT: I have everything working except I need a way as I can't find it: session.Process.Mute(); something like this that I can't find.