update docs

[mqhamdam]

When I logged in to GitHub on the server, I set up a passphrase, which made the workflow throw permission denied. Please take this scenario for installation steps too.
It's really hard to understand the SSH installation setup process.
some steps are unclear, Should I generate SSH on my local machine, or should SSH first to my remote server and then generate SSH keys?
what does mean below line code?
cat .ssh/id_rsa.pub | ssh b@B 'cat >> .ssh/authorized_keys'
what does b@B means? (git@github.com? username@remoteserveripaddress?)
and from which server I should run the above shell script?
-- Had to learn about private and public keys, and after 99 retries realized that my GitHub CLIhave passphrase