These skills you put points into all lead up to you learning helpful things like Customization, Training, etc.

While some of the skills seem useless like whistiling, it contirbutes to an overall skill. Whistling and, I think Animal Training or something, all lead up to the Familiar skill. It lets you send a bird on an errand to buy stuff while you are in the middle of a dungeon or something. Determination, Resilience, and Effort lead up to the valuable Training skill, a skill that lowers some of your attributes in return for more experience. You'll learn what skills help you learn what profession as you progress.

My advice would be to dump points into Determination. It lowers SP needed to learn skills and saves a LOT in the long run. After that, Purity. Why? Check your Fol after you max it out. Trust me, worth it. From there, develop how you think will benefit you. Or look up a guide.

As for combat, it is simple. Beat the tar out of the enemy. You can assign moves to L and R if you want, makes combat very easy sometimes. And yeah. Its as simple as tapping the X button. Sometimes you'll want to pull back in battle and run from the enemy. You can cancel actons with the square Button if it comes to that. If you want more freedom change the targeting to Semi Auto and move your character to the enemy you want to attack, the press X.

You'll get used to all this after a while. (I know I did.) And believe me, it is totally worth it. I love the game. If you like this one, pick up the second one. It is just an improved version. Well, the story for the second one is awful, but still REALLY good. If you have any more questions, feel free to ask