Git is a tool originally developed by Linus Torvalds himself. Github is one platform of many that uses Git. Similar to Gitlab, Bitbucket, Codeberg or Gitea. You can also directly use git without a platform around that.

As a developer you really should know that. That’s basics.

He means to ask if you tool is open sourced. If so, he wanted to look at the code

There’s other guy forges than GitHub. Like gitlab, codeberg, etc…