moving to Lightroom forum for assistance
Lightroom CC and Lightroom 6 are same version of application.
Lightroom 6 is a stand-alone application.
Lightroom CC is a subscription based product and has Dehaze, only feature which is not available in Lightroom 6.
If you have a catalog created in Lightroom 6, you will be able to use it in Ligthroom CC without any issues.
Also, in order to convert Lightroom 6 to Lightroom CC, you need to sign out from Lightroom 6 and sign back in using your email address registered with Adobe and has the subscription.
Hope this helps.
Thank you very much, yes, it helps !