When I do sudo apt-get update this is the output that I get.
Hit:1 https://deb.termius.com squeeze InRelease
Hit:2 http://repo.mysql.com/apt/ubuntu focal InRelease
Err:3 http://qa.old-releases.ubuntu.com/ubuntu focal InRelease
Could not resolve 'qa.old-releases.ubuntu.com'
Hit:4 http://dl.google.com/linux/chrome/deb stable InRelease
Err:5 http://qa.old-releases.ubuntu.com/ubuntu focal-updates InRelease
Could not resolve 'qa.old-releases.ubuntu.com'
Err:6 http://qa.old-releases.ubuntu.com/ubuntu focal-backports InRelease
Could not resolve 'qa.old-releases.ubuntu.com'
Hit:7 http://ppa.launchpad.net/alexlarsson/flatpak/ubuntu focal InRelease
Get:8 http://packages.microsoft.com/repos/edge stable InRelease [7,343 B]
Get:9 http://packages.microsoft.com/repos/code stable InRelease [10.4 kB]
Hit:10 https://cli.github.com/packages stable InRelease
Hit:11 http://ppa.launchpad.net/git-core/ppa/ubuntu focal InRelease
Ign:12 http://old-releases.ubuntu.com/ubuntu focal InRelease
Get:13 https://packages.microsoft.com/repos/azure-cli focal InRelease [10.4 kB]
Err:14 https://releases.librevault.com/debian focal InRelease
521 [IP: 172.67.202.232 443]
Ign:15 http://old-releases.ubuntu.com/ubuntu focal-security InRelease
Hit:16 http://ppa.launchpad.net/linrunner/tlp/ubuntu focal InRelease
Err:17 http://old-releases.ubuntu.com/ubuntu focal Release
404 Not Found [IP: 91.189.91.124 80]
Ign:19 http://ppa.launchpad.net/morphis/anbox-support/ubuntu focal InRelease
Get:20 https://download.sublimetext.com apt/stable/ InRelease [2,536 B]
Get:21 https://mega.nz/linux/MEGAsync/xUbuntu_20.04 ./ InRelease [2,441 B]
Err:22 http://old-releases.ubuntu.com/ubuntu focal-security Release
404 Not Found [IP: 91.189.91.124 80]
Err:23 http://ppa.launchpad.net/morphis/anbox-support/ubuntu focal Release
404 Not Found [IP: 91.189.95.85 80]
Hit:18 https://packagecloud.io/slacktechnologies/slack/debian jessie InRelease
Reading package lists... Done
E: Failed to fetch https://releases.librevault.com/debian/dists/focal/InRelease 521 [IP: 172.67.202.232 443]
E: The repository 'https://releases.librevault.com/debian focal InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: The repository 'http://old-releases.ubuntu.com/ubuntu focal Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: The repository 'http://old-releases.ubuntu.com/ubuntu focal-security Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: The repository 'http://ppa.launchpad.net/morphis/anbox-support/ubuntu focal Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
I looked up for solutions online, most of those questions were outdated versions of Ubuntu, but I am currently running on Ubuntu 20.04 LTS (End of life-April 2030). Why am I getting these errors? I tried some others solutions online, but one of them only made more errors than already existed. How do I solve this problem? Or how can I remove certain package links from the apt source list if not solve it?
