There are something like 6 skill books for each skill in the dlc + original game which is 18-24 points for each skill, in your travels you will at least visit the locations of most of these books, whether you find them or not is another thing. You should not have any issue maxing out every skill to 100 by level 50 with int around 7ish or higher, I don't think educated or comprehension are needed but IIRC I usually get one or the other for lack of good alternatives. Survival skill increases the amount of health you get from food and the amount of hydration you get from water(you will get more health from food and drink than anywhere else unlike fallout 3 where you are in stimpak heaven), it is pretty useful imo but more of a quality of life thing if you want to be harsh about it.