javascript – How do I add items to a SP2013 list from an HTML form?

I have a knowledge check in HTML form, so I cant inject into CEWP or SP pages. It needs to be JS, CSS, and HTML. How do I populate a list if someone completes a Knowledge Check? It will add the score, module#, name, and date to list ‘JAcerts’ upon completion.

Here is my check: https://jsfiddle.net/Lance_Bitner/6gkL92av/6/

This line needs to be the action where I submit, I think? When the cert taker hits this button I need their info to go to the list, ‘JAcerts’.

 <a id="btn" type="submit" onclick="window.location.href="https://sharepoint.stackexchange.com/#game-over"">Next</a>

Cert picture:

Check out my js in my jsfiddle. I HAVE TRIED so many JS codes but not connecting them correctly.

The list and Knowledge check are in the same site “/sites/OA03/Lists/JAcerts'” for the list and “sites/OA03/JA%20Training/” for Knowledge Check.