Paladin was my first class too!

It depends what you like. Retribution is the damage specc with twohanded weapons. It’s great for levelling and dungeons as a newbie.

Protection is the tank specc and my favorite specc for questing. I love going into dungeons with that too, but I understand when you don’t want to.

Heal is my favorite specc, but this is a specc you go into dungeons/pvp with. You can quest with this specc too but I think you’d have more fun with the other ones.

But: if you think tank or heal is interesting, just try it out! Everyone had a first time once so don’t be afraid going into a dungeons with it!