Setup your new EC2 instance on AWS and choose Amazon AMI.
SSH to your instance using your private key
ssh -i <path-to-your-pem-file> ec2-user@<ec2-endpoint-or-ip>
Change to root
sudo su
Create new group for your user ( in this case my group name is ‘dev’ )
groupadd dev
Create new user and assign it to your recently created group
useradd -g dev dev
Give the username root access
visudo
Add this to the bottom of the file
dev ALL=(ALL) NOPASSWD:ALL
Delete the password for ‘dev’ user
sudo passwd dev -d
Change to the ‘dev’ user
su dev
Try run sudo su whether you can gain root privileges
sudo su
Change user back to dev and set authorized_keys for ssh
exit
mkdir ~/.ssh
vi ~/.ssh/authorized_keys
chmod -R 700 ~/.ssh
If everything is correct, you should be able to change to root user from dev without providing any password.