update docs

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

Start by locating the SSH installation documentation and reviewing the setup steps described in this issue. Clarify where keys should be generated, what the passphrase workflow requires, what `b@B` represents, and which server runs the command; done means a newcomer can follow the installation without these ambiguities.

Written by the indexing model from the issue text.