This installs the latest podman version on a Linux Mint 21 system, using OpenSuse's kubic project's repositories.
mkdir -p /etc/apt/keyrings
curl -fsSL https://download.opensuse.org/repositories/devel:/kubic:/libcontainers:/unstable/xUbuntu_22.04/Release.key | gpg --dearmor | sudo tee /etc/apt/keyrings/devel_kubic_libcontainers_unstable.gpg > /dev/null
echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/devel_kubic_libcontainers_unstable.gpg] https://download.opensuse.org/repositories/devel:kubic:libcontainers:unstable/xUbuntu_22.04/ /" | sudo tee /etc/apt/sources.list.d/devel:kubic:libcontainers:unstable.list > /dev/null
apt update
apt install podman