CS6 Installer

What edition did you buy?  Was it purchased directly from Adobe or a 3rd party?  Depending on your license, these direct downloaders may or may not work with your serial number.

https://prodesigntools.com/adobe-cs6-direct-download-links.html

MODERN OPTIONS:
Photoshop Elements or Premier Elements (approx $100, no subscription needed)
https://www.adobe.com/products/photoshop-elements.html

Creative Cloud Photography Plan -- approx $10/month for 12 months. Includes the very latest versions of these great products & services:
-- Photoshop CC and Photoshop on iPad
-- Lightroom on desktop, mobile and the web
-- Lightroom Classic
-- Portfolio website + hosting
-- Spark with premium features
-- Bridge
-- 20 GB cloud storage (upgradable to 1 TB).
https://www.adobe.com/creativecloud/photography.html

Creative Cloud All Apps (31 + apps & services) and Single Apps Plans
https://www.adobe.com/creativecloud/plans.html

1 - IF you registered your serial number with Adobe

https://community.adobe.com/t5/download-install/download-non-subscription-adobe-software/td-p/11919842

2 - Direct Download Links https://prodesigntools.com/tag/ddl MAY help
-you MUST do what it says in Note: Very Important Instructions
-https://prodesigntools.com/adobe-cc-2015-direct-download-links.html#download-instructions
-the prodesign links go directly to Adobe's file server, so this process
--will only work until Adobe completely removes the old version(s) from the server
.
IF/When you do have a download, be sure to copy it to AT LEAST one external device
-since Adobe does sometimes remove old versions from the server
-a usb flash drive or hard drive, or write to a DVD
-plus a text file containing your serial number