SSH is a remote login program (secure shell). You use it to connect to other server's via a terminal.
It is recommended to setup an SSH key, with a config file and autocomplete so you can easily (and securely) connect to your servers.
You can login with a private key as below, however it is trivial enough to setup a config file and far easier once done - I highly recommend it!
ssh -i ~/.ssh/my_private_key username@hostname_or_ip_address.com
!!! Note: you must use two spaces in the below format - otherwise it won't work!
You can add as many hosts as you like in the following format.
host my_alias Hostname ip_address User ubuntu IdentityFile ~/.ssh/blah.pem IdentitiesOnly yes
Now, to connect to the above alias
my_alias, simply use:
Run the following and follow the prompts.