pool.json

{    "parameters": {
        "nodeCount": {
            "type": "int",
            "metadata": {
                "description": "The number of pool nodes"
            }
        },
        "poolId": {
            "type": "string",
            "metadata": {
                "description": "The pool ID "
            }
        }
    },
    "pool": {
        "type": "Microsoft.Batch/batchAccounts/pools",
        "apiVersion": "2016-12-01",
        "properties": {
            "id": "[parameters('poolId')]",
            "virtualMachineConfiguration": {
                "imageReference": {
                    "publisher": "microsoft-azure-batch",
                    "offer": "ubuntu-server-container",
                    "sku": "20-04-lts",
                    "version": "latest"
                },
                "nodeAgentSKUId": "batch.node.ubuntu 20.04",
		"containerConfiguration": {
			"containerImageNames":["hello-world:latest"]
			}
            },
            "vmSize": "STANDARD_D2s_V3",
            "targetDedicatedNodes": "[parameters('nodeCount')]",
            "enableAutoScale": false
            ]
        }
    }
}