Debian 11 Bullseye : Download
[1] Download Debian GNU/Linux 11 Bullseye ( released on 14
August, 2021 ) from the following site.
⇒ http://cdimage.debian.org/debian-cd/
Debian 11 Bullseye : Create an installation CD/DVD
After downloading ISO of Debian, Burn it to a DVD with an
burning application to create an installation disk. If you create it with the
function of Windows 7/8/10, refer to follows.
[2] Insert an empty DVD media in DVD drive. Next, right-click the ISO image of Debian and select [Burn Disk image] in the menu.
source: https://www.server-world.info/