This assumes you have already configured the aws command line tool. If not, check out my article on Getting Started with the AWS CLI.

The aws ec2 describe-flow-logs command can be used to list the Flow Logs you have created.

aws ec2 describe-flow-logs

Something like this should be returned.

[
    {
        "CreationTime": "2023-10-05T01:50:24.089000+00:00",
        "DeliverLogsPermissionArn": "arn:aws:iam::123456789012:role/publishFlowLogs",
        "DeliverLogsStatus": "SUCCESS",
        "FlowLogId": "fl-00f4bbdec6dd110c6",
        "FlowLogStatus": "ACTIVE",
        "LogGroupName": "RDSOSMetrics",
        "ResourceId": "vpc-0a9d4cb29e2748444",
        "TrafficType": "ALL",
        "LogDestinationType": "cloud-watch-logs",
        "LogFormat": "${version} ${account-id} ${interface-id} ${srcaddr} ${dstaddr} ${srcport} ${dstport} ${protocol} ${packets} ${bytes} ${start} ${end} ${action} ${log-status}",
        "Tags": [],
        "MaxAggregationInterval": 600
    }
]

Then the aws ec2 delete-flow-logs command can be used to delete the Flow Log.

aws ec2 delete-flow-logs --flow-log-id fl-00f4bbdec6dd110c6