I had accidently lost my data and wanted to start from this lesson and was finally able to do so after tinkering around. Hopefully this will help someone in the future:
After doing git clone in terminal into the directory, you can do git reset --hard SHA_ID, with the SHA_ID being to the right of the commit. Lesson 11 is fb5ae96da98a1d32932372254008e7f20f2cd23b.
This will set the version back to that commit.
If your prefabs aren’t showing, just right click on them and click Reimport, then load the Scene. You can now start at the specific commit