Since you are 18 and have graduated, you are likely an emancipated adult.
That means you can move out and take care of yourself, and your parents are no longer responsible for paying any of your bills. Until you move out, you are subject to their house rules, as would be any other guest.
Since you are now an adult, you should also perhaps consider the effects of your actions. Vaping causes harm to your lungs each time you inhale any heated fluid, and will inevitably leave you more susceptible to illness. When you have to go to work to support yourself, that has a much more serious affect. It also affects you when your health costs go up as a result of your needing more health care. Irritating lung tissue and then breathing in germs causes damage to your breathing apparatus, without which you cannot live.
You parents have every right to tell you it's time to pack your bags, and not just for college. Start your adult life by making smart decisions, because this one will definitely affect your success. But sure, you have every right to get out, and start damaging what you have been given. With your own money.