ChromeOS keeps taking up CPU usage to 100%, and messes with me running Linux apps, so I would like to remove ChromeOS and go Ubuntu-only. Linux was installed on this 14-ca052wm Chromebook using Crouton (more) and here's a screen shot from gparted 
of my 12 drive partitions.
I wanted to download Minecraft on Linux so I downloaded Java 7, because anything over Java 7 says
Could not find
so I installed Java 7, but when I try to update Java by entering:
sudo add-apt-repository ppa:webupd8team/java
it doesn't work. Neither does
sudo apt update; sudo apt install oracle-java8-installer
Do I need to install something else for Java to work?
I can't add any PPA'S at all, no matter what!
Please help!