SQL & PL/SQL

Hello,
I have the following JSON:

{
	"_nodes": {
		"total": 25,
		"successful": 25,
		"failed": 0
	},
	"cluster_name": "testcluster",
	"nodes": {
		"-7ECgmInS0yL75s8n10Bmw": {
			"timestamp": 1620895198060,
			"name": "node1",
			"transport_address": "10.6.142.134:9300",
			"host": "host1",
			"ip": "10.6.142.134:9300",
			"roles": [
				"data",
				"transform"
			],
			"attributes": {
				"disk": "ssd",
				"xpack.installed": "true",
				"zone": "MYZONE",
				"transform.node": "true"
			},
			"indices": {
				"search": {
					"open_contexts": 5,
					"query_total": 10
				}
			}
		},
		"TLIt5CKsSZKJ7HImhSVJSw": {
			"timestamp": 1620895198062,
			"name": "node2",
			"transport_address": "10.6.142.233:9300",
			"host": "host2",
			"ip": "10.6.142.233:9300",
			"roles": [
				"data",
				"transform"
			],
			"attributes": {
				"disk": "hdd",
				"xpack.installed": "true",
				"zone": "MYZONE",
				"transform.node": "true"
			},
			"indices": {
				"search": {
					"open_contexts": 15,
					"query_total": 20
				}
			}
		}
	}
}

and I would like to select values of open_contexts and query total from all nodes. The problem is that there is n nodes and I dont know the node names (in this case -7ECgmInS0yL75s8n10Bmw and TLIt5CKsSZKJ7HImhSVJSw) in advance.
Expected output would be

open_contexts           query_total
5                             10
15                            20

Any ideas would be highly appreciated.
Regards,
Pavel