While creating a Linux instance at Amazon EC2 you can choose to “Create and Download SSH Key” option which will let you download a PEM file (SSH Secure Key) on your local machine and you can use this SSH secure key while connecting your Linux instance at Amazon.
Once your Linux instance is ready and running at Amazon you can get instance URL from Amazon portal shown as below:
You can use iTerm/Terminal (Mac) or Putty/BitVise SSH client (Windows) applications to connect your Linux instance as below:
1. Change your PEM file permissions
$chmod -R 700 Downloads/your_instance_ssh_key.pem
2. Now you can use the ssh command to connect to your Linux instance by using -i parameter to use key:
$ ssh -i your_ssh_security_key.pem root@ec2-NN-NNN-N-NN.us-west-2.compute.amazonaws.com