you may find a situation where you want to access your Linux instance from someone's else machine, but your Linux need the .pem key file and you don't want to carry your .pem file to other's machine. why not just create a password for ssh, so let's create it

1) first you have to log in to your Linux box using .pem

$ ssh -i your_pem_file.pem ubuntu@ec2-________.compute-1.amazonaws.com

2) create a user that will access the instance using a password

$ sudo useradd -s /bin/bash -m -d /home/USERNAME  -g root USERNAME

3) create a strong password for the new created user

$ sudo passwd USERNAME
Enter new UNIX password:
Retype new UNIX password:

4) Add user to the sudoers file by using sudo visudo command

USERNAME  ALL=(ALL:ALL) ALL

5) Enable password authenticating by editing /etc/ssh/sshd_config file. and look for PasswordAuthentication

PasswordAuthentication no 
# change it to yes
PasswordAuthentication yes

6) restart ssh demaon

$ sudo systemctl restart ssh

You're done, let's login by password

$ ssh USERNAME@hostname

BOOM you dit it. Make sure to create a strong password as it's less secure using a password rather than .pem file.

Thank you so much for reading my article, I hope you got something to learn today. stay positive and happy coding.

anybody can succeed on the space, so don't listen to nay-sayer.