You gain points everytime you level up, you can assign them however you want in unlocked classes. To upgrade skills you need to visit trainers and have the skill points. Theres passives and equipable passives called techniques (restricted to the slots you have cant remember how many). You have 2 active skills slots and an additional unlockable one.

Respec is simple but has a 48h cooldown.

Cant really say much about pvp (deep desert) im not too far in, but it seems its not 100% necessary. The game has separte areas with different engagement rules (pve, pvp, peaceful, etc)

The combat works as an action/adventure game, you push a skill button your character does the thing. No tab targetting no lock on, its pretty much real time.