Most supports are pretty easy to play, although they can be boring. In comparison to league of legends though, it feels like supports can still have a rather large impact on the game as they aren't crucially item reliant, though items do help. Some relatively easy heroes that I like to use are crystal maiden, though her ult requires that you be in the middle of a fight to make use of it. Her other skills are a range aoe nuke and a range snare / freeze which are great for team fights if you can slow people. If you decide you want to try a carry, range is probably a bit more forgiving until you get the hang of things.