You can add remote repository to an existing git repo with the command: git remote add origin [URL_TO_YOUR_REPO]

So when you have a local Laravel project, in the project just init git: git init

Then add the remote: git remote add origin [URL_TO_YOUR_REPO]

Add all the files to git: git add .

Make a commit git commit

Push everything to your remote repository git push origin master

From that point you can easy make branches (Develop branch, Feature branch, release, etc.)

About your .gitignore, before you make the first 'git add .' you may want to update your .gitignore file so files and folders from your IDE etc. will not committed to git remote.

Hope this helps you!