Is it possible to remove all files in a repository and update it with only the files I have in my local machine? The reason is that, there are certain files that is not necessary in my github and so I want to remove those files. Instead of removing the files one by one, I wanted to see if its possible to just remove all files in my git repo and update/push with only the files in my local machine. Hope its clear. Thanks.
Yes, if you do a git rm <filename> and commit & push those changes. The file will disappear from the repository for that changeset and future commits.
The file will still be available for the previous revisions.