You can't push to github without an account. That's how github can validate that you have the rights to push. If that is a problem, host your own gitea instance.
Once you have an account, the way to do it is using ssh keys. Use ssh-keygen (or putty keygen) to generate a key pair, add the public key to your account, and the set up ~/.ssh/config.
If I understand OP's explanation correctly, they're simply trying to make a, possibly selfhosted, copy of a GitHub repo.
In that case the misunderstanding would be in the role of the git command; it being simply a frontend to any git repo, not a client to GitHub.
The correct commands to achieve that would be
$ git init .
$ git remote add origin url
$ git remote add github url
$ git fetch github
$ git merge github/master
$ git push -u origin master
There may be errors in the above code. I'm writing this from memory on my phone.
@Chais@sh.itjust.works
If I understand OP’s explanation correctly, they’re simply trying to make a, possibly selfhosted, copy of a GitHub repo.
git push origin masterDon't push.
I have no idea what you're actually trying to accomplish. What you're doing doesn't seem to match the description.
So what are you trying to do?
Yeah, sounds like an XY problem.
Learn how to use git with this open source game https://ohmygit.org/
If the repo is private you'd need to set up ssh keys with an account to pull, but pulling from public can be done anonymously
Clone over HTTPS, not git.
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