Debian Mirror Installation
To Change Mirror Manually You have to change your mirror address in /etc/apt/sources.list
After that run the sudo apt update command
Bardia Moshiri Mirror in Iran
For Debian 11
deb http://mirror.bardia.tech/debian bullseye main non-free contrib
deb http://mirror.bardia.tech/debian bullseye-updates main non-free contrib
deb http://mirror.bardia.tech/debian-security bullseye-security main contrib non-free
For Debian 10
deb http://mirror.bardia.tech/debian buster main non-free contrib
deb http://mirror.bardia.tech/debian buster-updates main non-free contrib
deb http://mirror.bardia.tech/debian-security buster-security main contrib non-free non-free contrib
For Debian 9
deb http://mirror.bardia.tech/debian stretch main
deb http://mirror.bardia.tech/debian stretch-updates main
deb http://mirror.bardia.tech/debian-security stretch-security main contrib non-free non-free contrib