Enable detailed monitoring for EC2 instance

No, enabling detailed monitoring will just provide data in 1-minute periods. It does not include metrics on memory usage. The available CloudWatch metrics for the basic monitoring (5-minute period) and detailed monitoring (1-minute period) can be found here: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html.

If you need to view memory usage metrics, you need to use a CloudWatch Agent. More details here: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/mon-scripts.html and https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/metrics-collected-by-CloudWatch-agent.html.

By default, Amazon EC2 metrics related to CPUUtilization, a set of disk Read and Write metrics, and a set of NetworkIn and NetworkOut can be fetched. But, EC2 doesn't provide metrics related to OS-level memory usage or disk usage metrics. You will need to configure custom metrics for memory. Please follow steps in this article to configure memory metrics. https://aws.amazon.com/premiumsupport/knowledge-center/cloudwatch-memory-metrics-ec2/#:~:text=By%20default%2C%20Amazon%20EC2%20delivers,usage%20or%20disk%20usage%20metrics.