下面给出的都是一件命令，如需详细信息请打开参考资料

将debian12源替换为清华大学源

echo "
# 默认注释了源码镜像以提高 apt update 速度，如有需要可自行取消注释
deb https://mirrors.tuna.tsinghua.edu.cn/debian/ bookworm main contrib non-free non-free-firmware
# deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ bookworm main contrib non-free non-free-firmware

deb https://mirrors.tuna.tsinghua.edu.cn/debian/ bookworm-updates main contrib non-free non-free-firmware
# deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ bookworm-updates main contrib non-free non-free-firmware

deb https://mirrors.tuna.tsinghua.edu.cn/debian/ bookworm-backports main contrib non-free non-free-firmware
# deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ bookworm-backports main contrib non-free non-free-firmware

deb https://security.debian.org/debian-security bookworm-security main contrib non-free non-free-firmware
# deb-src https://security.debian.org/debian-security bookworm-security main contrib non-free non-free-firmware
"> /etc/apt/sources.list

将pve源替换为清华大学源

echo "
deb https://mirrors.tuna.tsinghua.edu.cn/proxmox/debian/pve bookworm pve-no-subscription
" > /etc/apt/sources.list.d/pve-enterprise.list

参考资料：

https://mirrors.tuna.tsinghua.edu.cn/help/debian/
https://mirrors.tuna.tsinghua.edu.cn/help/proxmox/