My local repository was on git "Branch A" and had a number of untracked files, so what I did is created a new branch (let's call it "Branch B"), switched to that branch added those files to commit and pushed it to remote repo.
What I want to do now is to revert everything back, namely, make the files from last commit untracked again, switch to "Branch A" and delete "Branch B" completely on local and remote.
How can I do that?