fallingstar
You can use this as a chance to get the MC to actually look into how spells work. That way he will be able to make his own spells more easily later. Plus reading about how a skill works would boost the skill level. Using a skill book gives you basic understanding of something. But the book itself contains info that the Gamer would not unlock till they level up the skill. So by reading the same book after consuming it he should level the skill a few times. Anywhere between 20%-50% max level (this is up to you if you want to do it or not). Also with a better understanding of magic he will be able to level skills faster. So you can make the apprentice title for Sorcerer Require reading (actually reading) more books about the topic. You can even make a passive skill called understanding of magic. And one called understanding of chemistry. And one called understanding of mechanics. And so one, each one would give a passive boost to intelligence or wisdom or both. And would give a passive boost to any skills related to that area, and acquiring knowledge in that area becomes easier. Like with the language skill.