I never done that but I suppose that you could start from AWS CloudWatch | Documentation
There a link to Getting started: Monitor hosts with Elastic Observability | Starting with the Elasticsearch Platform and its Solutions [8.13] | Elastic
You said that the logs are coming from a lambda, right? So may be the best tool in that case is this one: Elastic Serverless Forwarder for AWS | Elastic Serverless Forwarder Guide | Elastic
But again I'm not an expert on that field... 