how to add .git in my folder code example

Example 1: add github repo

create a new repository on the command line
echo "# {Repo Name}" >> README.md
git init
git add README.md
git commit -m "first commit"
git branch -M main
git remote add origin https://github.com/cdcdianne/ReactJS-TheMovieDB.git
git push -u origin main
                
push an existing repository from the command line
git remote add origin https://github.com/cdcdianne/ReactJS-TheMovieDB.git
git branch -M main
git push -u origin main

Example 2: how to make a folder into git repo

$ git remote add origin git@github.com:username/new_repo
$ git push -u origin master