This text is some kind of personal notes I save here, but it may be useful for some people. Don't expect high quality writing here 😀.
Minecraft is quite slow and unoptimized, fortunately using the mod "Sodium", you get access to more advanced video settings that allow to reduce the computer power usage, or just make the game playable for older computers.
This requires PolyMC, a launcher for Minecraft which takes care of mods and other things. PolyMC is available on Linux and Windows.
In PolyMC:
Now, your Minecraft is using the Sodium mod, this allows greater choice within the "Video settings" like the Performance tab with more options.