i get a E:package has no installation candidate when installing any packages using apt-get

Question

ive tried apt-get update and upgrade but that fixes nothing.

ive looked at my sources.list:

eb http://ftp.debian.org/debian/ buster main contrib non-free
deb http://security.debian.org/ buster/updates main contrib non-free
deb http://ftp.debian.org/debian/ buster-updates main contrib non-free

# Uncomment lines below then 'apt-get update' to enable 'apt-get source'
#deb-src http://ftp.debian.org/debian/ buster main contrib non-free
#deb-src http://security.debian.org/ buster/updates main contrib non-free
#deb-src http://ftp.debian.org/debian/ buster-updates main contrib non-free

# 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.

and have no idea if those work or not. please help, ive been trying to find a fix for this for a while. im running the rpi os for desktop but this also happens with plain debian and other debian based distros as well.

Answer 1

You are running Debian - NOT Raspbian!

Even so - if you followed the recommended practice - using apt rather than apt-get you should be prompted to accept the changes.