Is there a way I can add a lock on tv startup, or just individually lock the apps, preferably without any third-party applications? I did manage to find a setting that says "Parental" which asks a password but nothing happens when I set it or change it and there are no other settings inside the menu.

Before anyone asks, the lock is for me. I want to stop myself from turning the tv on but not everyone else in the house. I have exams coming up and unless I lock myself out, I'll keep procrastinating.