Depends on where you live and your age, some countries need your parents consent if you are a minor. If you can get them without your parents knowing am sure you can take them without their knowing, but think long and hard about what you are about to do.
dont get one
Don't tell them.
pretend that your pregnent
By sneaking out at night when they are asleep, or saying that you are going somewhere else but you really aren't. Hope I helped!
If your Nuvaring comes out, then your chances of pregnancy are the same as any female without contraceptive protection.
wet the bed alot