I have a Creative Cloud Photography Plan, it should contain Photoshop CC and Lightroom 5.
I want to upgrade to lightroom 6 or lightroom CC in order to have Camera Raw 9 but I really don't know how to do it. Does someone can help me?
You can download and install the Lightroom CC from the Adobe Creative Cloud Desktop App.
Once you open the Creative Cloud App
Click on the App Section
Then, it will show you all the installed App and new updates as well.
You will see Lightroom CC 2015 listed there, so you can click on Install/Update to get the latest version.
Also, you can refer the System Requirement for Lightroom CC : System requirements for Adobe Lightroom for Mac and Windows OS
Let us know if that helps.