The only legitimate way to use Lightroom Classic for free is through a provided directly by Adobe. This version will be the most current release, which includes all the features of the 2021 version plus more recent AI-powered updates.

Adobe Lightroom Classic 2021 for Mac is a professional-grade photo editing and management tool. While you may find websites promising a "free download" for specific older versions like 2021, these are often unreliable and can expose your Mac to malware.