apt install gnupg1
# apt-transport-https
# no exist
ls -lF /usr/share/keyrings/helm*
ls -lF /etc/apt/sources.list.d/helm.list
curl https://baltocdn.com/helm/signing.asc -o /usr/share/keyrings/helm.asc
gpg1 --dearmor </usr/share/keyrings/helm.asc > /usr/share/keyrings/helm.gpg
distro=debian
distro=ubuntu
cat > /etc/apt/sources.list.d/helm.list <<EOF
deb [signed-by=/usr/share/keyrings/helm.gpg] https://baltocdn.com/helm/stable/$distro/ all main
EOF
apt update
apt install helm
https://helm.sh/docs/intro/install/
https://github.com/helm/examples/tree/main