How to add new ssh key to github

$ ssh-keygen -t rsa -b 4096 -C "[email protected]"
$ eval "$(ssh-agent -s)"
$ ssh-add ~/.ssh/id_rsa (regular unix system)
$ ssh-add -K ~/.ssh/id_rsa (for macbook)

$ pbcopy < ~/.ssh/ (for macbook)

Paste key into github

$ git remote add origin [email protected]:xxxxxx/xxxxxxx.git  
$ git remote -v 
$ git push -u origin master

How to GIT ERROR: Repository not found. ?

$ git push origin master

ERROR: Repository not found.
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
  and the repository exists.


Critical command line to address the issue –

Ensure ssh-agent is enabled:

Start the ssh-agent in the background

eval "$(ssh-agent -s)"