I want to install CS6

I have been using Adobe products, personally and professionally, for the past 30 years. I have had a few emails associated with Adobe accounts. Adobe Creative Cloud has been a nightmare for me since its introduction. I have an older iMac that runs OS Catalina. I can't upgrade the OS anymore. The Adobe apps are useless as they do not run or run very poorly on this machine. Previous to Adobe's subscription-based platform, I purchased the apps outright. The last one I bought was CS6. I would like to put it back on my computer and run it instead of all of the subscription-based apps. They do not work for me. I am having difficulty finding a way to download and install CS6 - even though a search online says it can be done - even from Adobe websites. I feel that I get run around in circles. Does anyone have a real answer on how to download and install CS6? I have my serial number.