Using the github saver probably won't teach you much about github.
The saver does work, but you have to be sure to fill in the "path" field even if you are using the root directory. For the root, use "/". This is unclear in the instructions.
The website publication option is interesting, but kind of a whole different subset of github. It allows you to produce a website using HTML and markdown, and the jekyll adds dynamic ability.
But if you're using TW, you already have dynamic ability.
You can combine the two aspects, so that you save your TW file to your own *.io website automatically. This means you could, in theory, sit down at
any browser in the world and access your own TW website. Since github is a MS product, it is more likely to be available even in facilities
that block youtube and gmail. The problem is that the whole world can also see your site, so it may not be so good if you're recording private information
such as names and addresses.
You can save to your own private directory, but you can't publish as a website from there, so if you were
sitting down at a new computer you would have to start by downloading the last committed instance of your tw file
from the github site.
So, the github saver is basically another saver. It's probably a good approach if you have a TW file that you want to conveniently
access and share with the world. But be sure to use a github token, and not a password, when setting it up. Also
remember that there is no real deleting with github. Each "commit" is stored forever, AFAIK.