Yes S3 can be used with EC2 instances:
Create the Amazon S3 File Gateway on the EC2 instance.
Create the VPC endpoints.
Generate the S3 File Gateway activation key.
Deploy S3 File Gateway.
Create the NFS file share.
Mount your NFS file share.
Stopping an instance is same as shutting down your machine and you can restart it and the persistent volume prevails. Terminating the instance is like destroying an instance, there is no turning back.
On-Demand Instances: Pay as you go
Reserved instances: Commit for 1-3 years
Spot instances: Get unused instances on upto 90% discount.
Start the SSH agent in you local computer. Add private key to your SSH Agent. SSH into the Baston host and then you can access your EC2 instances fron the Baston host.
Choose your instance and go to Actions-> Monitor and troubleshoot -> manage cloud watch alarms
choose create an alarm. Toggle to alarm actions and choose recover. choose other required options and create the alarm.