How can I commit the repository that I cloned to my GitHub as a new project via terminal?

I’m a freshman working on my oF homework and is stuck by commit the repository that I cloned to my GitHub as a new project via terminal. How to commit the repository that I cloned to my GitHub as a new project via terminal? I have finished the step of cloning my classmate’s repository. Can anyone help me with it?

check this site:
https://git-scm.com/docs/gittutorial

If you have already cloned the repo using

git clone https://REPOSITORY.git

Go to your folder and type (dot means all files, comment will be changed in the future commits)

git add .
git commit -m "Initial commit"
git push -u origin master