So, hit m on your keyboard, and a circle of symbols and a piece of paper with your stats shows up. Click the shopping bag icon in the circle of symbols, and reroll whatever category you want.
So, in the starting town, there is a job board. Click the first piece of paper on the left that says to kill the wolves (recommended for new players) slay the wolves, and you are likely going to get a spell for your book. If it doesn't give you a spell, do the quest until it gives you a spell.