There are pros and cons to each choice. When you buy in a store, you can see and try on the ring, which can give you a better idea of how it looks and how well-made it is. It also allows you to ask questions and get guidance from a salesperson. There may be more options and lower prices when you buy online, but it can be harder to tell if the ring is of good quality and the right size. If you decide to buy something online, do your research and buy from a seller with a good reputation. Look for reviews and ratings from other customers, and ensure you know how to return the ring if needed.