To rename a folder from oldName to newName

git mv directoryToFolder/oldName directoryToFolder/newName

Followed by git commit and/or git push

If this error occurs:

fatal: renaming 'directoryToFolder/oldName' failed: Invalid argument

Use the following command:

git mv directoryToFolder/oldName temp && git mv temp directoryToFolder/newName

You can rename branch in local repository using this command:

git branch -m old_name new_name

the easiest way is to have the local branch checked out:

git checkout old_branch

then rename the local branch, delete the old remote and set the new renamed branch as upstream:

git branch -m new_branch
git push origin :old_branch
git push --set-upstream origin new_branch