fatal: remote origin already exists.

I have created a local git repository for an RStudio project. When I use git remote add origin..., using the code given by you all, I get the following error:

fatal: remote origin already exists.

Then, when I try git push -u origin --all, I get the following:

Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

I can see the repo I created on the Bitbucket website, but I'm not sure if it's a firewall issue on my end.

Thanks,
Will