fatal: 'origin' does not appear to be a git repository

try this

git remote add origin <https://github.com/"username"/"repository".git> 

then try to again

git push -u origin master

When you run git clone <repo_url> to clone a repository, the default remote origin is created automatically. If the repository is created by git init, there is no default remote, no origin. You need to set it up by yourself.

git remote add origin <repo_url>

repo_url is the path to an existing remote repository which you want to exchange data with . If it's in the local disk, it could be file:///home/me/foo.git or /home/me/foo.git. If it's hosted in Github, it could be https://github.com/me/foo.git or ssh://[email protected]/me/foo.git.

As to the 2nd error about "fetch first". You need to run git pull origin <branch> or git pull -r origin <branch> before a next push.

I had this same error message while trying to do a PR. On a critical look, I realized I was carrying out the Git workflow on a wrong directory.

In my case, I simply went back a step to the right dir using **cd..** and then proceeded with no more error.

git remote add origin <url>

then

git push -u origin master