notebook is a 10 year old macbook pro without macos I installed xubuntu 24.04 in. It comes with an embedded battery.
First notebook I bought, not from apple, had a removable battery. The vendor told me to maximize its life I shouldn’t plug the battery in, unless I need it (like for traveling). This way, I’ve managed to keep the original battery in good working condition for 8 years so far.
Back to the macbook: I cannot remove the battery and constantly loading it to up to 80% and discharge it up to 20% seems ridiculous. Furthermore, this would deplete the battery even faster, I believe.
What can I do to spare the battery as much as possible?
For linux it depends. For example, you can modify the maximum charge on ASUS laptops. There’s also this wonderful tool called asusctl [https://asus-linux.org/] that modifies allows you to more effectively use your laptop. Here is the arch wiki page for it: https://wiki.archlinux.org/title/ASUS_Linux . Do note that, unfortunately, the only officially supported distros are Arch and Fedora, but you can make it work with some effort.
TLP is my favourite tool for messing with the charge limit. And also far, far too many power/thermal management knobs.