"You have a certain amount of power, which you can simplify slightly and say is a certain number of 'units', which isn't the smallest amount of potential power you could possibly put into something, but is the smallest thing that can clearly and legibly entirely power the smallest bits of magic on offer. Looks like you have about 25 of those, which is about what I'd expect from rank-4 potential. I mentioned there's a cap to how much you can get - yours is probably about 80, maybe 85; mine was 60 and I've gotten pretty close to hitting it. Anything that you have an elemental affinity for costs half as much. Anything that is connected to your class costs two units less, or gives you two units more, and the first rank of things costs one unit to start with, so you can and probably should take all the elementalisms you can see at rank 1 and you'll gain power from it. Power you gain that way, or from the ordinary drawbacks, doesn't count toward the cap, it's like a separate pool. Small magic and drawbacks have a set cost; ranked magic increases in cost for each rank, one two three four, and the class boost just applies to the first rank. If you have a matching class and element, you get the whole stack for less than half the cost for someone with neither."
"Elementalisms are specific - either you have the element, or you have one particular pair of other elements that make it up like Wind and Metal for Fire, or you don't. Non-elementalism magics are either universal and act like everyone matches them, like 'witchery' which means 'messing with your mothergifts and their extradimensional storage space', or they have three elements associated with them. So, for example, if you want to get a familiar that's exotic or smarter than a clever dog, you can learn 'familiarity', which has affinity for Beast, Soul, or Nature, and is a sorceress magic."
"All the factions have some magic associated with them, and they'll teach it to you about twice as fast as if you find some other way to study it. I can't help you pick those up now unless you accept a Fate that ties you to the faction - you wouldn't have to stay forever but you would have to join and be a member in good standing for years, or you'd get backlash, which usually manifests as random drawbacks that you're then stuck with. Otherwise they're like normal non-elemental magic. Don't study Outsider magic, obviously."