That first part is eerily similar to what I was about to post.
In 2011, I was a lonely introvert. I spent my time binging TV shows and reading.
In 2012, on an IRL meetup thread on the 4chan x (paranormal stories) board, I met a new friend. I think deciding to meet them was the critical moment. They introduced me to a local arts and crafts club, a certain sci-fi fandom, and Minecraft.
The arts and crafts club became the basis of a friend group that is still my main friend group today. They brought me to a local convention in 2013 where I discovered I was trans.
In that sci-fi fandom, at a 2016 convention, I met my current partner, and a bunch of new friends.
I played a lot of Minecraft from 2012 to 2016, but then my partner in 2016 introduced me to Factorio.
The easiest way to disable unnecessary services is to uninstall them with aptitude, or whichever package manager you like. Try terminating services one by one, and see if anything bad happens. If nothing bad happens, you can probably uninstall it. On the other hand, if the system does get wonky a reboot should fix it. Or, you can research the services by name and decide whether to uninstall them. (avahi-daemon for example is a good idea to uninstall.)
To make the GUI not run, uninstall your display manager (gdm, xdm, nodm, or whatever) and uninstall your xorg server or wayland server. There may be GUI programs remaining after that, but they will only be consuming disk space, not RAM or CPU.
If the battery is old and holds little charge, you may save a few watts by removing it and throwing it away, instead of letting the system keep it topped off.
Get a power meter, such as a Kill-a-watt device. Then, experiment with different settings. If it’s consuming less than 30 watts, you’re probably fine. If you live in the US, one watt-year is about one US dollar (or a little more), so for every watt it consumes, that’s about how much you will pay per year for its electricity.