StartingIf you have no idea what your first build will be, just ask from here ->
http://forum.fonline-reloaded.net/index.php?board=4.0For first build I recommend basic shooter SG or EW with Fast Shot.
If you get bored alone, I suggest to get friends ingame. Not everyone is bad and evil.
Quests or killing some enemies?Quests are easy way to get experience and caps for adventures, check quests from here ->
http://www.fonline-reloaded.net/wiki/index.php?title=QuestsYou can easily get lvl 6 atleast from finishing quests, after that you are good enough to go kill some enemies.
Also remember to put all caps to bank account (cost 100caps, in almost all big towns like NCR, HUB...)
Keep leveling up and become strongAfter you get used to game and know how to kill, be ready for hard level up and become strong.
Molerats can be killed with any character that use guns,
Ghouls are little tough and do more critical hits than other enemies, but they are good experience and you get some weapons from them.
Good luck!Maybe little short, but yeah I'm too bored to write about all I've learned. It would take too long.
You need experience it yourself, and learn.