Just a warning. The skill system, sadly gives leeway for faster leveling schemes. So most people there, follow a certain skill path to level as fast as possible, then use drugs to revert to what they really wanna play.
It was one of the reasons I left, there's barely any midlevel gameplay for characters that don't go for fast leveling. There used to be, but once the population started to die off, only the real 'leet' addicts remained, so that's what you get.
But if you really want to enjoy the game, pick something you -like- and stick with it, go playing normally, find some people who feel the same way and group with them. The reason for that is that you not only learn skills from using them, but from watching your group mates using them. So if you're a pistol guy and you're grouping with a psychic dude, you will get psy xp from watching him use his powers and he will get pistol xp from watching you. The bigger the team, the more you get. Also, learn how to craft/recycle as soon as possible. Every single container, and I really really mean every single container in the game that you see on the streets, is a random loot box. If you see a box by a store, open it and you will find loot. It may seem like crap, like rotten food, insect parts, and body parts, but if you know how to recycle and craft, those meaningless parts can be your drugs and ammo of tomorrow.