Create intent in Unity

// Initialize AndroidJavaClass with full name of the Intent class.
AndroidJavaClass intentClass = new AndroidJavaClass("com.mygame.pkg.MyClass");

// Get context (activity)
using (var jc = new AndroidJavaClass("com.unity3d.player.UnityPlayer"))
{
    using (var activity = jc.GetStatic<AndroidJavaObject>("currentActivity"))
    {
        // Equivalent of calling the Intent(Context, Class<?>) constructor.
        var intent = new AndroidJavaObject("android.content.Intent", activity, intentClass);

        // launch intent (using context)
        activity.Call(intent);
    }
}