Hi & welcome to YT!!! I don't crate train mine alot of people do. My SIL does & swears by it hers goes to their crate on their own when she leaves to. If you have a fenced in yard where no other dogs go potty I think it would be fine to take your pup out. Dogs usually don't get parvo in winter as it lives in the ground & if the ground is cold & froze it is dormant. Good luck with your furbaby.
Their is alot of informative people on here that give good advise you'll find youself on here for hours.
