Use Custom Apex Domain for GitHub Pages site with DNS in WordPress

Just a gentle reminder that I am a complete novice on this subject, so any help would be greatly appreciated.

What I am trying to do is have a domain name that is registered through WordPress, and have a website on Github Pages, but have the domain name on WordPress go through to the site on Github. And I think I am supposed to do this with a combination of Alias or A records as well as CNAMES, and there’s also something to do with DNS whatnots and something else, but I seem to be stuck going through the WordPress manuals to no success.

Essentially, I needed to host a website, so I decided to just buy a personal plan through wordpress which comes with a domain name from WordPress. When I realized WordPress wasn’t going to allow me to actually write the CSS for my website, I decided to find an alternate solution. Turns out, Github Pages was exactly what I wanted. They would allow me to completely host my own site, exactly the way I wanted it. However, they don’t provide the custom domain names, but they allow you to link through via CNAME s, which, being a complete novice, I have no idea what these are. I went in to Github Pages where it says "Custom Domains" typed in my custom domain, then it gives me a green check: enter image description here This is accomplished through navigating over to WordPress, and with the following configuration: (I’m too lazy to color out my website name anymore so) enter image description here So I went through all of the steps to configure this, including going through Github’s posted manuals on managing a custom domain as found here, and WordPress’s manuals on how to do this as found here. I really don’t know what I am doing, but any help would be greatly appreciated. Thank you.