There are lots of files here! Do I need all of them? In most cases it is not necessary to download and use all of these images to be able to install Debian on your computer. Debian comes with a massive set of software packages, hence why it takes so many disks for a complete set. Most typical users only need a small subset of those software packages.
Initially, you will only need to download and use the first image of a set (labelled as debian-something-1 to be able to start the Debian installer and set up Debian on your computer. If there are more images available here (labelled debian-something-2, debian-something-3, etc.), they contain the extra packages that can be installed on a Debian system (as mentioned previously). They will not be bootable and are entirely optional. If you have a fast Internet connection, you're most likely better off installing any desired extra packages directly from the Debian mirrors on the Internet instead of by using these extra images.
# 2.添加国内能快速访问的镜像源，这里选择腾讯。修改完成后，保存退出到命令行 deb http://mirrors.cloud.tencent.com/debian/ buster main non-free contrib deb http://mirrors.cloud.tencent.com/debian-security buster/updates main deb http://mirrors.cloud.tencent.com/debian/ buster-updates main non-free contrib deb http://mirrors.cloud.tencent.com/debian/ buster-backports main non-free contrib deb-src http://mirrors.cloud.tencent.com/debian-security buster/updates main deb-src http://mirrors.cloud.tencent.com/debian/ buster main non-free contrib deb-src http://mirrors.cloud.tencent.com/debian/ buster-updates main non-free contrib deb-src http://mirrors.cloud.tencent.com/debian/ buster-backports main non-free contrib
