How to Add a new SSH key to your GitHub account on Ubuntu 18.04

Step 1: Generating a new SSH key and adding it to the ssh-agent

              ssh-keygen -t rsa -b 4096 -C "your_email@example.com"

Step 2: Enter 3 times

Step 3 : eval "$(ssh-agent -s)"

Step 4 : ssh-add ~/.ssh/id_rsa

Step 5: sudo apt-get install xclip

Step 6 : xclip -sel clip < ~/.ssh/id_rsa.pub

Step 7: Sign In Your Github account

Step 8 : go to settings -> SSH and  GPG Keys -> click New SSH key -> Right Click(Ctrl+V) Paste Key