GitHub is a great place to pubslish your code; and it is often required to post code there when learning to code. If you are writing a NodeJS app and being required to publish code to GitHub you should be careful of pushing any code that contains secret API keys. These keys could be scraped and used to write apps with your keys.
Don't have time to read all the stuff below. I get it. Add:
export KEY=value
export ANOTHER_KEY=anothervalue