An Elastic Load Balancer (ELB) is typically used to load balance requests across two (or more) different EC2 instances. 

The aws elbv2 describe-load-balancers command can be used to list the Elastic Load Balancers that have been created. 

aws elbv2 describe-load-balancers

And here is an example of how to limit the output using the --query option.

aws elbv2 describe-load-balancers --query 'LoadBalancers[?LoadBalancerName==`my-load-balancer`]'

Optionally, the --load-balancer-arns option can be used to return one or more Load Balancers matching the provided ARNs (Amazon Resource Number).

aws elbv2 describe-load-balancers --load-balancer-name my-load-arns arn:aws:elasticloadbalancing:us-east-1:123456789012:loadbalancer/app/my-load-balancer/ffd90871234abcde

Something like this should be returned.

{
    "LoadBalancers": [
        {
            "LoadBalancerArn": "arn:aws:elasticloadbalancing:us-east-1:123456789012:loadbalancer/app/my-load-balancer/ffd90871234abcde",
            "DNSName": "my-load-balancer-371234535.us-east-1.elb.amazonaws.com",
            "CanonicalHostedZoneId": "Z35SXDOTRQ7X7K",
            "CreatedTime": "2023-03-28T01:23:28.410000+00:00",
            "LoadBalancerName": "my-load-balancer",
            "Scheme": "internet-facing",
            "VpcId": "vpc-014d2fcfa335d3c01",
            "State": {
                "Code": "active"
            },
            "Type": "application",
            "AvailabilityZones": [
                {
                    "ZoneName": "us-east-1b",
                    "SubnetId": "subnet-03f11411234f6abcd",
                    "LoadBalancerAddresses": []
                },
                {
                    "ZoneName": "us-east-1a",
                    "SubnetId": "subnet-03123451234f7ab34",
                    "LoadBalancerAddresses": []
                }
            ],
            "SecurityGroups": [
                "sg-0c3296123415abcd1"
            ],
            "IpAddressType": "ipv4"
        }
    ]
}