Vampirism

Ok so i am new to this whole scripting thing and i would prefer to do it myself rather than ask people since i would feel more accomplished doing it so. However i have no idea where to begin and i am hoping someone could give me some starting info on how to do this. What i am looking for is trying to create a spell system similar to the vampire class in bravely default. basically you only learn the spells through seeing them in combat rather than books or level up. Also a summoning mechanic that is similar but you learn them upon defeating an enemy. i have tried searching for awhile and couldn't find anything even remotely similar so i thought i would ask here. Again not asking for a whole script or anything like that just a good direction to get started.