On a mac it’s easy to get started. Open terminal by pressing CMD ⌘ + spacebar to open Spotlight Search and type terminal, then press enter to open it.
In terminal just type the following replacing it with a valid IP or your hostname (often just your domain!) then enter your password when promoted.
ssh [email protected]
Congrats! Your now connected to your server via SSH. TL;DR Replace the username with yours and the IP address with your server. Then enter the password when prompted. Note: Sometimes host change the default port 23 to something else and this is where you need to add the modifier followed by the port number. Looking for alternative to Terminal on the mac try iTerm 2 for more customisation and powerful features.
Some Commands to learn:
cd, ls, mkdir, cp, rm, mv, wget, yum, service, tail, vim vs nano, tar, unzip, gzip