Ich bin mit den angezeigten Meldungen total überfordert. Wäre es nicht gescheiter Ubuntu neu zu installieren? Wenn ja, bitte ich um Anleitung.
2. Teil
deb https://de.archive.ubuntu.com/ubuntu/ focal-security main restricted
# deb-src https://security.ubuntu.com/ubuntu eoan-security main restricted
deb https://de.archive.ubuntu.com/ubuntu/ focal-security universe
# deb-src https://security.ubuntu.com/ubuntu eoan-security universe
deb https://de.archive.ubuntu.com/ubuntu/ focal-security multiverse
# deb-src https://security.ubuntu.com/ubuntu eoan-security multiverse
# This system was installed using small removable media
# (e.g. netinst, live or single CD). The matching „deb cdrom“
# entries were disabled at the end of the installation process.
# For information about how to configure apt package sources,
# see the sources.list(5) manual.
# deb https://dl.winehq.org/wine-builds/ubuntu/ focal main
# deb-src https://dl.winehq.org/wine-builds/ubuntu/ focal main
deb https://security.ubuntu.com/ubuntu/ focal-security multiverse restricted universe main
# deb-src https://archive.ubuntu.com/ubuntu focal main«.
Die ersten 5 Zeilen müßten im 1. Teil schon vorhanden sein