I can creat a new file in Git with the echo command:
echo > newFile.txt
git init from the directory where the files live. This creates a repository for your code.
You can then
git add and
git commit your files.
Following that, add an
origin pointing to BitBucket so you can push your code.
git remote add origin git@bitbucket/path/bitbucket/gives/you/for/your/repo
git push -u origin master will create the master branch on the remote for the first time.