Wireguard error

I thought docker was an alternative to LXC.

I installed the docker engine using the instructions on https://docs.docker.com/engine/install/debian/
I believe Proxmox is based on debian.

cat /etc/os-release
PRETTY_NAME="Debian GNU/Linux 11 (bullseye)"
NAME="Debian GNU/Linux"
VERSION_ID="11"
VERSION="11 (bullseye)"
VERSION_CODENAME=bullseye
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"

If I am misunderstanding is there a link you can refer me to?
Thanks