Welcome to the Ranch
I suggest you stop using Eclipse at this stage, and use a decent text editor, e.g. NotePad+, Notepad2, jEdit,
not Microsoft Notepad.
Create a “Java” or similar folder and put all your work in that.
Copy all the Stanford classes into the same folder structure as you are working in probably with their highest‑level folder named to match the package names (maybe “edu”).
Write out the programs in text. Write import declarations for any of the Stanford classes you need to use.
t will be rather like HelloWorld or
MooseGreetings, only bigger.