What you want to do is:
git commit -am "Message for my commit"
This will automatically add all tracked files and you can type your message in one command.
-a –all
Tell the command to automatically stage files that have been modified and deleted, but new files you have not told Git about are not affected.
-m <msg> –message=<msg>
Use the given as the commit message. If multiple -m options are given, their values are concatenated as separate paragraphs.
https://git-scm.com/docs/git-commit
If you want to stage and commit untracked files, you can:
git add -A && git commit -am 'message'