这个对我来说很有用(需要的时候留作参考)

# Go into your existing directory and run below commands
cd docker-spring-boot
echo "# docker-spring-boot" >> README.md
git init
git add -A
git commit -m "first commit"
git branch -M master
git remote add origin https://github.com/devopsmaster/docker-spring-boot.git
git push -u origin master
                

首先，用你的项目名在Github上创建一个新的存储库。然后按照以下步骤。

1)git init
2)git add *
3)git commit -m "first commit"
4)git remote add origin https://github.com/yuvraj777/GDriveDemo.git
5)git push -u origin master

我不想再补充另一个答案，但我的特定场景在这里没有完全涵盖。我有一个本地回购，其中有我想保存的更改历史，还有一个在Github上为我创建的非空回购(即默认的README.md)。是的，你总是可以将Github回购重新创建为空回购，但在我的情况下，其他人有权限创建这个特定的回购，如果有一个简单的解决方案，我不想麻烦他。

在这种情况下，当你在设置远程源后尝试git push时，你会遇到这个错误:

 ! [rejected]        master -> master (fetch first)
error: failed to push some refs to 'git@github.com:<my repo>.git'
hint: Updates were rejected because the remote contains work that you do
hint: not have locally. This is usually caused by another repository pushing
hint: to the same ref. You may want to first integrate the remote changes
hint: (e.g., 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.

正如错误所示，我需要在设置远程原点后执行git拉取，但我需要指定——allow-unrelated-histories选项。如果没有这个选项，git pull会发出警告:没有共同提交。

下面是对我有效的命令序列:

git remote add origin <github repo url>
cp README.md README.md-save
git pull origin master --allow-unrelated-histories
mv README.md-save README.md
git commit -a
git push

我知道，这是一个老问题，但我试图解释每一步，所以它可以帮助别人。这是我如何添加一个现有的源代码到git:

Create the repo on the git, so you'll have the ssh || https where you're gonna remote add you source code. In your terminal go to the path of your project. Run git init (here you initiate the project as a git one). Run git add * (here you add all the files and folders from you project). Run git commit -m "Initial Commit." (here you commit your files and folders added in step #4; keep in mention that you can't push your changes without committing them). Run git remote add origin https://your_username@bitbucket.org/your_username/project-name.git (here you add a remote project where your source it's gonna be pushed; replace my link with your ssh || https from the step #1). Run git push -u origin master (here you push your source into the git repository).

注意:这些都是将源代码推入主分支的简单步骤。

Follow below gitbash commands to push the folder files on github repository :-
1.) $ git init
2.) $ git cd D:\FileFolderName
3.) $ git status
4.) If needed to switch the git branch, use this command : 
    $ git checkout -b DesiredBranch
5.) $ git add .
6.) $ git commit -m "added a new folder"
7.) $ git push -f https://github.com/username/MyTestApp.git TestBranch
    (i.e git push origin branch)

创建一个新的存储库

git clone <url>
cd "repositoryName"
touch README.md
git add README.md
git commit -m "add README"
git push -u origin master

现有的文件夹

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

现有Git存储库

cd existing_repo
git remote rename origin old-origin
git remote add origin <url>
git push -u origin --all
git push -u origin --tags