Sign in at manage.autodesk.com and navigate to the Products & Services tab. Expand the AutoCAD 2024 tile and click View Details to see your unique serial number.

While is the most common key, different versions of the software require specific codes: Autodesk 2024 Product Keys - Microsol Resources

Check your inbox for a message from Autodesk (often titled "Fulfillment Notification") sent at the time of purchase.