Get active Window or Process Title Programatically

Hi Team, I used below code to get active window details. but unable to find title of it. Can you please help me on it.

C# based code in Mac

var foreground_app = NSWorkspace.SharedWorkspace.FrontmostApplication;

foreground_app contains active application details. but i am not able to identify active window details . guide me which property or function i need to use to get active window title details

EX: i opened Numbers, below condition will trigger

if(foreground_app.LocalizedName.ToLower().Contains("numbers")) {

/// }