This video will shows how to enable SSH in Ubuntu 18.04 LTS.
Ubuntu provides OpenSSH (OpenBSD Secure Shell) in its universe repositories, which is a suite of security-related network-level utilities based on the SSH protocol.
1. To install it, open terminal (Ctrl+Alt+T) or log in Ubuntu server and run command:
sudo apt-get install openssh-server
2. After that, you should have SSH service enabled in your system, you may check its status by running command:
sudo service ssh status
3. You may change some settings (e.g., the listening port, and root login permission) by editing the configuration file via command:
sudo nano /etc/ssh/sshd_config
sudo service ssh status
sudo nano /etc/ssh/sshd_config
sudo service ssh restart