How to purchase USDD?

Could you please elaborate on the steps involved in purchasing USDD? I'm new to the world of cryptocurrency and am keen on understanding the process. Could you begin with identifying the platforms or exchanges that support USDD trading? Also, would you mind explaining the process of setting up an account on such a platform? Furthermore, how do I ensure the safety of my transactions? What are the fees associated with purchasing USDD? And finally, could you provide any tips or advice for a beginner like me to navigate the cryptocurrency market successfully? Thank you for your assistance.