NTA I think however, depending on how your parents will react, it is or it is not ine your best interest to find the right time. If they can become angry and decide to stop funding your college, you can wait until you graduate. Or if they will think you quitting church means you are raking downhill to their etes, they could be guarding you, try to restrict you. If they are not r/insaneparents you can tell them any time. They should respect the fact, just like you respect them being religious. If they don't understand, don't expect much, or don't loose ypur energy to try and change their minds and accept you. Maybr time will do it, if it ever happens.