`git remote` Manage the other copies of your repository

Lists and edits the named links to other copies, usually on GitHub. The default link created by git clone is called origin.

Synopsis

git remote [-v]
git remote add NAME URL
git remote set-url NAME URL

Option or form	What it does
`-v`	Show each remote with its fetch and push addresses
`add NAME URL`	Add a new remote
`remove NAME`	Delete a remote
`rename OLD NEW`	Rename a remote
`set-url NAME URL`	Change a remote's address
`show NAME`	Describe a remote and its branches

See where you push and pull

git remote -v

origin	https://github.com/ana/site.git (fetch)
origin	https://github.com/ana/site.git (push)

Link a local repository to GitHub

git remote add origin [email protected]:ana/site.git

Add the original project after forking

git remote add upstream https://github.com/octocat/Hello-World.git

Switch from https to ssh

git remote set-url origin [email protected]:ana/site.git

The names are only labels. origin is a convention, and upstream is the usual name for the project you forked from.
A remote holds no files itself. It is just a saved address.
gh repo fork can add the upstream remote for you.