Type of Ranger
The build type really depends on your weapon choice and your play style. There is no cookie cutter build tho. I used short bow, all the way to level 80, because I love the fast paced, and mobility aspect of it, the dmg is decent also. The traits were power and precision mainly. If you level up and you have a general idea about how to avoid getting hits by mobs you don’t have to focus on defensive stuff. Just kite and nuke everything.
About the armor, idk if there is anything special for level 20, maybe a crafted medium armor, but you will be fine with the gear you get from karma vendors. Just buy those stuff.
Do you know what type of traits you have?