have you already tried it?
What is you concrete problem?
If you have already tried, you could provide some code snippets and explain what you are struggeling with? (edit: you edited the question and added some code snippets, I’ll have a look at them now)
From the distance it sounds like you are running into the CORS trap.
You need a backend service that fetches the json for you running on the same origin as you page is served from. This answer is a good starting point đŸ™‚
Hope this helps.
edit: Had a look at your snippets and it is like I assumed: you have a problem with CORS. Your javascript is not allowed to load data from any arbitrary URL.