Newbie Guide:
Skills are divided into active skill and passive skills. Active skills, including spells, must be intentionally used. Passive skills, on the other hand, permanently increase your basic abilities.
First, learn active offensive skills. It will be good to learn a skill that restores your HP while damaging your enemies. There's a Toggle Skill that you can use to turn the effect on and off. You will be consuming MP when it's on, so make sure you only use it when you need to.