Code for your project should be in a public Github repository. You can use any repo name you like. Link to your repo should be in your final report, presentation, and poster.
Github Tutorial
You can find the official Github tutorial here. You might also find this Github tutorial helpful. If you prefer video tutorial, this short youtube video might be useful.
Git
Github uses Git. Git is a version control system. You can find a Git tutorial here. You can also find a Git tutorial here.