You cannot push code to repositories that you don’t own or have sufficient permission to. So instead, you make your own copy of the repository by “forking” it. You are then free to make any changes you wish to your repository.
What is padleft?
Can you explain one more time what command " --set-upstream-to=upstream/master master" does? My guess is whenever you do "git pull origin master" it will pull the latest changes from upstream master and not from your copy