create branch from existing repository git code example
Example 1: git new branch
$ git checkout -b [your_branch_name]
# Switched to a new branch [your_branch_name]
# This is shorthand for:
$ git branch [your_branch_name]
$ git checkout [your_branch_name]
Example 2: git create new repo from branch
$ git push https://github.com/accountname/new_repo.git +old_branch:master