Getting started with unit testing

I'm new to Javascript (not new to programming) and been working away building my first project. I have it up on GitHub and currently have no unit tests. When I started poking around it looks like there are a bunch of different testing frameworks. What should I try out first to set up CI on Github? Also, a simple repo that is a good example would be great. Honestly, I want a whole setup with coverage reporting and VSCode compatible linting too.

If it makes a difference, the project is a webpage, where the user uploads a binary file (a saved game), the page allows modifications, then serializes it back into a binary format for downloading.