how to generate ssh key in linux
ssh-keygen -t rsa -b 4096
ssh-keygen -t dsa
ssh-keygen -t ecdsa -b 521
ssh-keygen -t ed25519
Source: www.ssh.com
ubuntu generate ssh key
ssh-keygen -t rsa -C "your_email@example.com"
Source: confluence.atlassian.com
ubuntu add public key to server
ssh-copy-id -i ~/.ssh/id_rsa.pub user@server
Source: codegrepper