Photoshop CS5 me for MAC

Which Mac OS?  Legacy Creative Suite is 32-bit.  It can't run much less install on Catalina, Big Sur or Monterey.  Those systems support 64-bit software only.

Also Creative Suite Installers won't work on Sierra, High Sierra or Mojave without terminal workarounds.

https://helpx.adobe.com/creative-cloud/kb/install-creative-suite-mac-os-sierra.html

Keep in mind that CS5 is outdated and unsupported software from 2010.  Use at your own risk.

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Whch operating system are you running?

I do not know how far back this process will go, but try this link
-NOTE that you will have to search the site for your specific download
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 external hard drive, or write to a DVD
-plus a text file containing your serial number if you have a serial number program

As far as I know, big sur (or maybe it is catalina) and later are not compatible

Adobe does NOT do support by email, so beware of answering anyone who sends you a private message
-click for more information about scammers https://tinyurl.com/10791730