celle la ne me semble pas correct, mais je ne suis pas un expert…
voici mon source.list :
> deb http://deb.debian.org/debian/ buster main
> deb-src http://deb.debian.org/debian/ buster main
>
> deb http://security.debian.org/debian-security buster/updates main
> deb-src http://security.debian.org/debian-security buster/updates main
>
> #buster-updates, previously known as 'volatile'
> deb http://deb.debian.org/debian/ buster-updates main
> deb-src http://deb.debian.org/debian/ buster-updates main
>
> #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.
Regarde là au cas où :