git全局配置用戶
git config --global user.name “xxx”
git config --global user.email “xxx.cn”

情況1、存在git倉庫

git clone url.git
//cd xx
//touch README.md
//git add README.md
//git commit -m "add README"
//git push -u origin master

情況2、已存在文件夾，但沒有提交到git倉庫

cd existing_folder
git init
git remote add origin url.git
git add .
git commit -m "Initial commit"
git push -u origin master

情況3、創建分支？(未嘗試)

cd existing_repo
git remote rename origin old-origin
git remote add origin xxx.git
git push -u origin --all
git push -u origin --tags