Access AWS Management Console

In the Athena interface

In the Manage query result location and encryption section

Next step
kms-key-s3-<account-id>-<region>-an
s3://kms-key-s3-<account-id>-<region>-an/, then press Save
Go back to the Query editor section
cloudtrail_logs_kms_key_s3_<account-id>_<aws_region>_an_cloudtrail)

Try querying the eventname of the kms-key-s3-<account-id>-<region>-an log
SELECT eventname FROM "default"."cloudtrail_logs_kms_key_s3_<account-id>_<aws_region>_an_cloudtrail" LIMIT 100;

The above is an example of querying data. You can query anything you need in Query results.