//Get an ICLRMetaHost, an ICLRRuntimeInfo, an ICorDebug and then call ICorDebug.Initialize()
var corDebug = new CorDebug();

var callback = new CorDebugManagedCallback();

//You use event handlers for some, none, or all events
callback.OnAnyEvent += (s, e) =>
{
    Console.WriteLine(e.Kind);
    e.Controller.Continue(false);
};

corDebug.SetManagedHandler(callback);

//Use the CreateProcess() extension method that omits lpApplicationName and contains optional parameters
var process = corDebug.CreateProcess("powershell.exe", dwCreationFlags: CreateProcessFlags.CREATE_NEW_CONSOLE);

while (true)
    Thread.Sleep(1);