Is there is plan to buy a older versions of adobe programs (cc2017 for example)?
No... Adobe offers the current and ONE older version
When you have a subscription you MAY be able to find an older version at this link, but even if you do find what you need, you still must have a subscription for the program to run
Direct Download Links https://prodesigntools.com/tag/ddl MAY help
-you MUST do what it says in Note: Very Important 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
So you mean I can download an older version as I want from this website (prodesigntools.com), and use my creative cloud subscription to run the program when I setup it, right?
It means you can use older versions IF your computer supports them AND also supports modern Creative Cloud system requirements. That can be a slippery tightrope. Check each one.
Yes that is right in addition to the following points.