Minha sugestão de sources.list para o Debian 11 (Bullseye)

Utilizando apenas softwares 100% livres.

Após entrar no terminal como root
#nano /etc/apt/sources.list

Copiar o conteúdo entre as linhas

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deb http://ftp.br.debian.org/debian/ bullseye main
#deb-src http://ftp.br.debian.org/debian/ bullseye main

deb http://ftp.br.debian.org/debian/ bullseye-updates main
#deb-src http://ftp.br.debian.org/debian/ bullseye-updates main

deb http://security.debian.org/ bullseye-security main
#deb-src http://security.debian.org/ bullseye-security main

#deb http://ftp.debian.org/debian bullseye-backports main
#deb-src http://ftp.debian.org/debian bullseye-backports main
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