If you like to setup a cloud-init template in Proxmox you can use this unattended installer.
cd ./debian-11/
./build-iso.sh
Upload debian-${version}-netinst-unattended.iso
to your Proxmox storage and install your cloud-init template.
I recommend an automated .iso upload with the Terraform module danitso/proxmox
and VM build with the proxmox Packer module.
You can find a build automation on terraform base in ./build
. First adjust the variables in the config files then build with terraform apply
.