>wonder if I can use my old version of adobe programmes
CS6 and earlier programs have not been tested and will not be updated for Mac El Capitan/Sierra
-which means that you try to use CS6 and earlier at YOUR risk of having problems
-https://helpx.adobe.com/creative-cloud/kb/install-creative-suite-mac-os-sierra.html
Serial number programs are no longer sold, so if your old program will not work with Sierra, you will need a Cloud Subscription
-EXCEPT Adobe Elements bundle | Adobe Photoshop Elements 15 & Adobe Premiere Elements 15 work with Sierra
Owners of old programs simply have problems with Mac El Capitan/Sierra... none of which is Adobe's fault... Adobe did not change your old program to make it stop working... Apple changed their operating system and THAT is why your old programs may not work, not because of anything Adobe did... Also... every time Apple issues an update, there is the risk that an old program that HAS been working will STOP working... bottom line, old programs require a matching old operating system