If you are on a modern Mac, you may need to look into Lightroom 6 (the last 64-bit standalone version) or the Creative Cloud subscription.
Many photographers argue that the older interface was less cluttered. Lightroom 3.6 focused on the core "Library" and "Develop" modules without the distractions of cloud syncing, social media sharing integrations, or mobile companion apps. It is a tool designed purely for desktop photography. Download Adobe Lightroom 3.6 For Mac
archive.org (The Internet Archive) hosts verified, clean copies of the Lightroom 3.6 trial. You would still need your own serial number to unlock it beyond 30 days. If you are on a modern Mac, you