Install SSM Agent on an Amazon EC2 during launch by Raj Gupta

1. Launch an Instance Using AWS console
2. On the Configure Instance Details page, expand Advanced Details.
3. For User data, choose As text. In the User data box, type information according to your Linux distribution requirements.

For RHEL7 and Amazon Linux 2:

#!/bin/bash
cd /tmp
sudo yum install -y https://s3.amazonaws.com/ec2-downloads-windows/SSMAgent/latest/linux_amd64/amazon-ssm-agent.rpm
sudo systemctl start amazon-ssm-agent

 For Amazon Linux:

#!/bin/bash
cd /tmp
sudo yum install -y https://s3.amazonaws.com/ec2-downloads-windows/SSMAgent/latest/linux_amd64/amazon-ssm-agent.rpm
sudo start amazon-ssm-agent

4. Finish adding other parameters, such as storage, tags, security group, and so on.

5. Launch your instance.

Now in your EC2 server SSM Agent already install.