How to link project created here to a Git Repo branch ?

I do not want to create a new repo. I already have a repo of the same project I've re-created here. I'd like to create a branch which refers to this version. Thanks!

I'm not sure I understand exactly what you've done and what you want to do, but maybe you need to do something like this?

# add your existing repo as a remote called "origin"
git remote add origin <url-to-your-existing-repo>
# fetch the contents of the remote repo.  they will now exist as, eg, /origin/master
git fetch origin
# create a new local branch
git checkout -b my-branch-name
# commit your local changes onto a local branch
git add .
git commit -m "current state of files on pythonanywhere"
# push your local branch up to origin, with the -u flag to set it as a tracking branch
git push -u origin my-branch-name
# compare the differences between your local branch and the remote version
git diff my-branch-name origin/master

Etc etc. Git takes a bit of getting used to, but once you do, it's very flexible and powerful. There's lots of good help on google and stackoverflow...