i am very new to Linux and currently very frustrated.
I was trying to install Metagoofil in the first place but it turned out, that I can't install anything or update, mostprobably because of wrong links in the
sources.list. Is this the reason for the problem?
I tried fixing this by editing the document by navigating into the file with the GUI but I couldn't save it due to missing rights...
So I watched tutorials. I found a tutorial that editet the document with nano/etc/apt/sources.List but when I safed there was actually a new file create
while the sources.list file i had made the changes on remained unchanged ..
I provided a picture with the troublemesssage.

Thank u in advance for reading my bad englisch if you have any questions please don't hesitate to ask.