Answers online range from “they don’t do much damage against netherite armor” to “use a shield” or “fight them with bow and arrow”. But you don’t start with any of those things and it can take a long time until you obtain them.
I mean right at the beginning, where you haven’t found any iron yet and therefore can’t craft a shield or armor. There legitimately doesn’t seem to be any reliable way to kill them without losing half your health. And they are EVERYWHERE. The only thing I can do is run away and dig a hole or pillar into the sky and wait until dawn, and if it’s raining even that doesn’t work.
I have no problems fighting zombies or spiders or creepers. But skeletons are like 1000x harder. What gives?
Prioritize a bed.