Since official channels are closed, many users turn to third-party file-sharing websites or torrent networks. This approach carries severe risks:

When prompted for license type, select (not “I have a serial number”). Enter a valid email address – this is only for Autodesk registration, not activation.

Downloading AutoCAD 2012: Current Status and Availability AutoCAD 2012 is a retired product and is no longer officially available for trial download through standard Autodesk channels

Still possible to download a free trial?? - Autodesk Community

AutoCAD 2012 introduced several major enhancements that streamlined the transition from 2D drafting to 3D modeling. For many professionals, it represents a "sweet spot" of performance and reliability before software moved heavily into cloud-connected ecosystems. Key Features Introduced in 2012

Autodesk offers a fully functional, free 30-day trial of the latest version of AutoCAD. This gives you immediate access to the most secure, feature-rich drafting toolset available without compatibility issues. Navigate to the official Autodesk website. Select the AutoCAD product page.

However, you can still find relevant content and alternative ways to access or install the software if you have existing credentials: Official Trials and Alternatives