If you installed docker you have full access to the host system and can add any other containers to docker that you want… you just can’t use the Supervisor to add them in Home Assistant. Almost all the HA addons can be installed via docker manually. You seem to fundamentally misunderstand all this.
If you want HA addons then install either Home Assistant OS or Home Assistant Supervised which both give you the addon store instead of HA Container that you have.