I am a new Ubuntu user and I am struggling with what I've discovered to be the widespread "login loop" issue, in which logging in immediately pops up a black screen and then returns to the login. I've tried numerous of the proposed approaches including using the terminal to clean and autoclean, but with no success. I'm nearly certain the reason this is happening is due to my root partition being full, however I don't know how to address this without access to my desktop environment. I also am uncertain why my root partition fille dup so quickly in the first place as I was getting warning messages about "low disk space on file system root" for a while despite many sources suggesting creating a root partition size of only 15-20 GB.

Please let me know if you have any suggestions