remove files in local
commit your chnages
push your chnages to github
you can refere here how to remove files from git-git remove untracked files
One easy way: download and install git from "https://git-scm.com/download/win". In windows explorer, go to the folder you want, right-click and run "Git bash here".
For those looking for a git solution (command line solution):
1. Manually delete the files just like you would normally delete any file in windows. Right click the file(s) and click delete.
2. Type this command
git add -u
You may go ahead and commit the change.