By the way, I found an effective way to deal with them. You need a morning star, a shield, and you need to position yourself in one spot above the stairs leading down into the cave. A strong hit will send them flying into the abyss, and sometimes they even fall on their own, including the fat skeletons. I got a good level boost from them at the beginning. It's true that I didn't always survive, but that seems to be normal in this game.
When I played for the first time, I got stuck not on the skeletons, but on the black knight. In the end, I also passed the game on the third try.
I should try playing it again, because last time I stopped somewhere in the sewers.