Testar codigo

I have a project of a friend (programming student): build a website that allows a search mechanism for publications in google books

They have only been studying programming for 2 months. Have seen html and css. They are using gitHub (personally this text editor seems obsolete)

My question is :

How do I link all the code that I have designed so that the result appears in google books?

. It has happened to me on several occasions, they have suggested downloading programs. I don’t know much about the subject, but it seems like a program is missing to download to my pc, or to acquire a license