I am unable to find enable custom container options in my databricks workspace admin setting.
Screenshot of Databricks workspace setting:
At the moment you can only do this via API/CLI/Terraform. Here is an example of the API code.
curl --request PATCH "https://${DATABRICKS_HOST}/api/2.0/workspace-conf" \
--header "Authorization: Bearer ${DATABRICKS_TOKEN}" \
--data '{ "enableDcs": "true" }'
More info can be found at https://docs.databricks.com/en/clusters/custom-containers.html#enable